NetScaler SDX 12

Last Modified: Sep 3, 2017 @ 11:00 am

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Overview

CItrix CTX226732 Introduction to Citrix NetScaler SDX.

NetScaler SDX is normal NetScaler hardware, but runs XenServer hypervisor, and several virtual machines:

  • Service VM (aka Management Service, aka SVM) – every SDX comes with this Virtual Machine. This VM enables the SDX Administrator to create additional VMs on XenServer.
    • It’s not possible to build this VM yourself. If it something happens to it, your only choice is to do a factory reset on the physical appliance, which deletes all local virtual machines, and recreates the Service VM.
    • Each Service VM only manages the VMs on the local SDX. Each SDX has its own Service VM. To manage multiple SDXs, use NetScaler MAS.
    • XenServer on SDX is a special build. Do not attempt to directly upgrade XenServer, patch XenServer, configure XenServer, etc. Instead, all upgrades and configurations should be performed by the Service VM.
  • NetScaler VPX Instances – you create one or more NetScaler instances on top of XenServer
    • The number of NetScaler instances you can create is limited by your SDX license.
    • The physical resources (CPU, Memory, NICs, SSL Chips, FIPS HSM) of the SDX are partitioned to the different instances.
    • The amount of bandwidth (throughput) available to the VPX instances depends on your license. For example, the 14040 SDX license gives you 40 Gbps of throughput, which is partitioned across the instances.
    • The NetScaler instances are created from a normal XenServer .xva template.
    • Each VPX has its own NSIP. Once the VPX is provisioned, you connect to the NSIP, and configure it like a normal NetScaler.

If the top left of the window says SDX, then you are logged into the Management Service (aka Service VM, aka SVM). If it says VPX, then you are logged into an instance.

High Availability – NetScaler SDX does not have any High Availability capability at the XenServer or SVM layer. In other words, every SDX is completely standalone. To achieve HA, you create NetScaler VPX instances on two separate SDXs, and pair the VPX instances in the normal fashion.

Why NetScaler VPX on top of SDX instead of normal hypervisors?

  • VPX on SDX gets physical access to SSL chips. These SSL ASICs are not available on normal hypervisors. SSL Chips provide significantly higher SSL throughput than normal hypervisors.
  • VPX on SDX gets SR-IOV access to the Network interfaces. This enables full 40 Gbps throughput to a single VM.
  • The SDX NICs can filter VLANs to different instances, thus ensuring that VPX instances cannot cross security boundaries by adding the wrong VLANs.
  • Some SDXs have Hardware Security Modules (HSM) for FIPS compliance. The VPXs on SDX can utilize this hardware security resource.

SDX Networking

  • Management port – Every SDX has a 0/1 port. The SVM and XenServer management IP are on this NIC. You need a minimum of two IPs on a management network connected to the 0/1 port. SVM and XenServer cannot use any of the data ports for management.
  • LOM port – Every SDX has a Lights Out Management (LOM) port. This port gives you out-of-band console access to XenServer. Once you’re on XenServer, you can use Xen commands to see the SVM console, and/or VPX consoles.
  • Data ports – The remaining interfaces can be aggregated into port channels. Port channels are configured at XenServer, and not from inside the VPXs. Use the Service VM to create channels, and then connect the VPXs to the channels.
  • VPX networking – When VPXs are created, you specify which physical ports to connect it to.
    • If you want the VPX NSIP to be on the same subnet as SVM and XenServer, then connect the VPX to 0/1.
    • Connect the VPX to one or more LA/x interfaces (port channels).
    • Once the VPX is created, log into it, and create VLAN objects in the normal fashion. VLAN tagging is handled by the VPX, not XenServer.
    • On SVM, when creating the VPX instance, you can specify a list of allowed VLANs. The VPX administrator is only allowed to add VLANs that are in this list.
  • SVM to NSIP – SVM must be able to communicate with every VPX NSIP. If VPX NSIP is on a different subnet than SVM, then ensure that routing/firewall allows this connection.

LOM IP Configuration

There are two ways to set the IP address of the Lights Out Module (LOM):

  • Crossover Ethernet cable from a laptop with an IP address in the 192.168.1.0 network.
  • ipmitool from the NetScaler SDX XenServer command line
    • For MPX, you can run ipmitool from the BSD shell.

Ipmitool Method:

  1. For NetScaler SDX, SSH to the XenServer IP address (this is not the Service VM IP).
    1. For NetScaler MPX, SSH to the NetScaler NSIP.
  2. Default XenServer credentials are root/nsroot.
    1. Default MPX credentials are nsroot/nsroot.
  3. If MPX, run shell. XenServer is already in the shell.
  4. Run the following:
    ipmitool lan set 1 ipaddr x.x.x.x
    ipmitool lan set 1 netmask 255.255.255.0
    ipmitool lan set 1 defgw ipaddr x.x.x.x

  5. You should now be able to connect to the LOM using a browser.

Laptop method:

  1. Configure a laptop with static IP address 192.168.1.10 and connect it to the Lights Out Module port.
  2. In a Web browser, type the IP address of the LOM port. For initial configuration, type the LOM port’s default address: http://192.168.1.3
  3. In the User Name and Password boxes, type the administrator credentials. The default username and password are nsroot/nsroot.
  4. In the Menu bar, click Configuration, and then click Network.
  5. Under Options, click Network, and type values for the following parameters:
    1. IP Address—The IP address of the LOM port.
    2. Subnet Mask—The mask used to define the subnet of the LOM port.
    3. Default Gateway—The IP address of the router that connects the appliance to the network.
  6. Click Save.
  7. Disconnect the laptop, and instead connect a cable from a switch to the Lights Out Module.

LOM Firmware Upgrade

The LOM firmware at https://www.citrix.com/downloads/netscaler-adc/components/lom-firmware-upgrade differs depending on the hardware platform. The LOM firmware for the 8000 series is different than the 11000 series and the 14000 series. Do not mix them up.

While this article focuses on SDX, note that NetScaler MDX has a new method for updating LOM as detailed at CTX218264 How to Upgrade the LOM Firmware on Any NetScaler MPX Platform

The SDX Update Bundle does not include LOM firmware update so you must update it separately:

  1. Determine which firmware level you are currently running. You can point your browser to the LOM and login to the see the firmware level. Or you can run ipmitool mc info from the XenServer shell.
  2. If your LOM firmware is older than 3.0.2, follow the instructions at http://support.citrix.com/article/CTX137970 to upgrade the firmware.
  3. If your LOM firmware is version 3.02 or later, follow the instructions at http://support.citrix.com/article/CTX140270 to upgrade the firmware. This procedure is shown below.
  4. Now that the firmware is version 3.0.2 or later, you can upgrade to 3.39. Click the Maintenance menu and then click Firmware Update.
  5. On the right, click Enter Update Mode.
  6. Click OK when prompted to enter update mode.
  7. Click Choose File, and browse to the extracted bin file.
  8. After the file is uploaded, click Upload Firmware.
  9. Click Start Upgrade.
  10. The Upgrade progress will be displayed.
  11. After upgrade is complete, click OK to acknowledge the 1 minute message.
  12. The LOM will reboot.
  13. After the reboot, login and notice that the LOM firmware is now 3.39.

SDX IP Configuration

Default IP for Management Service is 192.168.100.1/16 bound to interface 0/1. Use a laptop with crossover cable to reconfigure the IP. Point your browser to http://192.168.100.1. Default login is nsroot/nsroot.

Default IP for XenServer is 192.168.100.2/16. Default login is root/nsroot. Note: XenServer IP and Management Service IP must be on the same subnet.

There should be no need to connect to XenServer directly. Instead, all XenServer configuration (e.g. create new VM) is performed through the Management Service (SVM).

To change the XenServer IP, make the change through the SVM as detailed below:

  1. Point a browser to http://192.168.100.1, and login as nsroot/nsroot.
  2. When you first login to the SDX Management Service, the Welcome! Wizard appears. Click Management Network.
  3. Configure the IP addresses.
    1. Appliance Management IP = SVM (Management Service). This is the IP you’ll normally use to manage SDX.
    2. Application supportability IP = XenServer. You’ll almost never connect to this IP.
    3. The bottom has an Additional DNS checkbox that lets you enter more DNS servers.
    4. You can change the nsroot password at this time, or change it later after LDAP is configured.
  4. Click Done.
  5. Click the System Settings box.
  6. Enter a Host Name.
  7. Select the time zone, and click Continue.
  8. Click the Licenses box.
  9. Click Add New License.
  10. Allocate NetScaler SDX licenses normally.
    1. The SDX license defines the number of instances you can create.
    2. It also defines the amount of throughput available to the instances.
    3. The SDX license is allocated to ANY, which means you can use the same license on all SDX hardware, assuming all of them are purchased with the same license model.
  11. After uploading, click Finish and it should apply automatically.
  12. Or you can click Apply Licenses.
  13. Then click Continue.

Another way to change the Management Service IP address is through the serial port. This is actually the XenServer Dom0 console. Once logged in to XenServer, run ssh 169.254.0.10 to access the Management Service virtual machine. Then follow instructions at http://support.citrix.com/article/CTX130496 to change the IP.

The console of the Management Service virtual machine can be reached by running the following command in the XenServer Dom0 shell (SSH or console):

xe vm-list params=name-label,dom-id name-label="Management Service VM"

Then run /usr/lib64/xen/bin/xenconsole <dom-id>

SDX Platform Software Bundle

If your NetScaler SDX is not version 11 or newer, and if your NetScaler SDX is running 10.5 build 57 or later, then do the following:

  1. Go to Management Service > Software Images, and upload the Single Bundle for 12.0. The single bundle is around 1.3 GB.
  2. On the left, click System. On the right, click Upgrade Management Service. Select the Single Bundle upgrade file you already uploaded.
  3. Management Service will upgrade and reboot. A few minutes after that, XenServer will be upgraded. Be patient as there’s no notification that the box will reboot again.

Starting with SDX 11.0, all updates are bundled together and installed at once.

  1. Make sure your Management Service (SVM) is running SDX 11.0 or newer.
  2. Download the latest SDX Platform Software bundle from Downloads > NetScaler ADC > Release 12.0 > Service Delivery Appliances.

  3. Login to the SDX Management Service, go to Configuration > System.
  4. On the right, in the right column, click Upgrade Appliance.
  5. Browse to the build-sdx-12.0.tgz software bundle, and click OK.
  6. It should show you the estimated installation time. Check boxes next to the instances that need configs saved. Click Upgrade.
  7. Click Yes to continue with the upgrade.
  8. The Management Service displays installation progress.
  9. Once the upgrade is complete, click Login.

  10. If you click the Configuration tab, the Information page will be displayed showing the version of XenServer, Management Service (Build), etc.

DNS Servers

Older versions of SDX only let you enter one DNS server. To add more, do the following:

  1. In the Management Service, on the left, click System.
  2. On the right, click Network Configuration.
  3. On the bottom, there’s a checkbox for Additional DNS that lets you put in more DNS servers.
  4. Click OK when done.

Management Service NTP

  1. On the Configuration tab, in the navigation pane, expand System, and then click NTP Servers.
  2. To add a new NTP server, in the right pane, click Add.
  3. In the Create NTP Server dialog box, enter the NTP server name (e.g. pool.ntp.org), and click Create.
  4. Click Yes when prompted to restart NTP Synchronization.
  5. In the right pane, click NTP Synchronization.
  6. In the NTP Synchronization dialog box, select Enable NTP Sync. Click OK.
  7. Click Yes when asked to restart the Management Service. This only restarts the SVM. Other instances on the same box won’t be affected.

Management Service Alerting

Syslog

  1. On the Configuration tab, expand System > Auditing, and click Syslog Servers.
  2. In the right pane, click the Add button.

    1. Enter a name for the Syslog server.
    2. Enter the IP address of the Syslog server.
    3. Change the Choose Log Level section to Custom, and select log levels.
  3. Click Create.
  4. On the right is Syslog Parameters.
  5. You can configure the Date Format and Time Zone. Click OK.

Mail Notification

  1. On the Configuration tab, expand System > Notifications, and click Email.
  2. In the right pane, on the Email Servers tab, click Add.
  3. Enter the DNS name of the mail server, and click Create.
  4. In the right pane, switch to the Email Distribution List tab, and click Add.
  5. In the Create Email Distribution List page:
    1. Enter a name for the mail profile.
    2. Select the Email Server to use.
    3. Enter the destination email address (distribution list).
  6. Click Create.

System SNMP

  1. Go to System > SNMP.
  2. On the right, click Configure SNMP MIB.
  3. Enter asset information, and click OK. Your SNMP management software will read this information.
  4. Under the SNMP node, configure normal SNMP including: Trap Destinations, Managers, Alarms, etc.

  5. MIBs can be downloaded from the Downloads tab.

Instance SNMP

  1. The instances will send SNMP traps to the Service VM. To get alerted for these traps, in the Configuration page, in the navigation pane, expand NetScaler, expand Events, and click Event Rules.
  2. On the right, click Add.

    1. Give the rule a name.
    2. Select the Major and Critical severities, and move them to the right.
    3. Scroll down.
    4. For the other sections, if you don’t configure anything then you will receive alerts for all of the devices, categories, and failure objects. If you configure any of them, then only the configured entities will be alerted.
    5. Scroll down.
    6. Click Save.
  3. Select an Email Distribution List, and click Done.

Management Service nsroot Password and AAA

Change nsroot password

  1. On the Configuration tab, in the navigation pane, expand System, expand User Administration, and then click Users.
  2. On the right, in the Users pane, right-click the nsroot user account, and then click Edit.
  3. In the Configure System User dialog box, check the box next to Change Password.
  4. In Password and Confirm Password, enter the password of your choice. Click OK.

AAA Authentication

To enable LDAP authentication for the Service VM:

  1. Go to Configuration > System > Authentication > LDAP.
  2. In the right pane, click Add.
  3. This is configured identically to NetScaler.
    1. Enter a Load Balancing VIP for LDAP servers.
    2. Change the Security Type to SSL, and Port to 636.
    3. Scroll down.
    4. Note: if you want to Validate LDAP Certificate, then there are special instructions for installing the root certificate on the SVM. See Installing CA certificates to the SDX/SVM for LDAPS user authentication at Citrix Discussions for details.
    5. Enter the Base DN in LDAP format.
    6. Enter the bind account in UPN format, or Domain\Username format, or DN format.
    7. Check the box for Enable Change Password.
    8. Click Retrieve Attributes, and scroll down.
    9. For Server Logon Attribute, select sAMAccountName.
    10. For Group Attribute, select memberOf.
    11. For Sub Attribute Name, select CN.
    12. To prevent unauthorized users from logging in, configure a Search Filter as detailed in the LDAP post. Scroll down.
  4. Click Create.
  5. Expand System, expand User Administration, and click Groups.
  6. On the right, click Add.
  7. In the Create System Group page:
    1. Enter the case sensitive name of the Active Directory group.
    2. Check the box next to System Access.
    3. Configure the Session Timeout.
  8. Click Create.
  9. On the left, under System, click User Administration.
  10. On the right, click User Lockout Configuration.

    1. If desired, check the box next to Enable User Lockout, and configure the maximum logon attempts. Click OK.
  11. On the left, under System, click Authentication.
  12. On the right, click Authentication Configuration.

    1. Change the Server Type drop-down to EXTERNAL, and click Insert.
    2. Select the LDAP server you created earlier, and click OK.
    3. Make sure Enable fallback is enabled, and click OK.

SSL Certificate and Encryption

Replace SDX Management Service Certificate

To replace the Management Service certificate:

  1. PEM format: The certificate must be in PEM format. The Management Service does not provide any mechanism for converting a PFX file to PEM. You can convert from PFX to PEM by using the Import PKCS#12 task in a NetScaler instance.
  2. On the left, click System.
  3. On the right, in the left column, in the Set Up Appliance section, click Install SSL Certificate.
  4. Select the certificate and key files in PEM format. If the key file is encrypted, enter the password. Then click OK.
  5. The Management Service will restart. Only the SVM restarts; the NetScaler instances do not restart.


Force HTTPS to the Management Service

  1. Connect to the SVM using HTTPS. You can’t make this upcoming change if you are connected using HTTP.
  2. On the Configuration tab, click System.
  3. On the right, click Change System Settings.
  4. Check the box next to Secure Access Only, and click OK. This forces you to use HTTPS to connect to the Management Service.

SSL Encrypt Management Service to NetScaler Communication

From http://support.citrix.com/article/CTX134973: Communication from the Management Service to the NetScaler VPX instances is HTTP by default. If you want to configure HTTPS access for the NetScaler VPX instances, then you have to secure the network traffic between the Management Service and NetScaler VPX instances. If you do not secure the network traffic from the Management Service configuration, then the NetScaler VPX Instance State appears as Out of Service and the Status shows Inventory from instance failed.

  1. Log on to the Management Service .
  2. On the Configuration tab, click System.
  3. On the right, click Change System Settings.
  4. Change the Communication with NetScaler Instance drop-down to https, as shown in the following screen shot:
  5. Run the following command on the NetScaler VPX instance, to change the Management Access (-gui) to SECUREONLY:

set ns ip ipaddress -gui SECUREONLY

Or in the NetScaler instance management GUI, go to Network > IPs, edit the NSIP, and then check the box next to Secure access only.

SDX/XenServer LACP Channels

For an overview of NetScaler SDX networking, see Citrix CTX226732 Introduction to Citrix NetScaler SDX

To use LACP, configure Channels in the Management Service, which creates them in XenServer. Then when provisioning an instance, connect it to the Channel.

  1. In the Management Service, on the Configuration tab, expand System, and click Channels.
  2. On the right, click Add.
  3. In the Create Channel page:
    1. Select a Channel ID.
    2. For Type, select LACP or STATIC. If using Cisco vPC, then LACP is required. The other two options are for switch independent load balancing.
    3. In the Interfaces section, move the Channel Member interfaces to the right by clicking the plus icon.
    4. In the Settings section, for LACP you can select Long or Short, depending on switch configuration. Long is the default.
  4. Click Create when done.
  5. Click Yes when asked to proceed.
  6. The channel will then be created on XenServer.

VPX Instances – Provision

Admin profile

Admin profiles specify the nsroot user credentials for the instances. Management Service uses these nsroot credentials later when communicating with the instances to retrieve configuration data.

The default admin profile for an instance specifies a user name of nsroot, and the password is also nsroot. To specify a different nsroot password, create a new admin profile.

  • You can create a single admin profile that is used by all instances. To delegate administration, don’t give out the nsroot password to the instance administrators. One option is to enable LDAP inside the instance before granting access to a different department.
  • When creating an instance, there’s an option to create a non-nsroot account, which has almost the same permissions as nsroot, but leaves out some SDX specific features (e.g interfaces). This is another option for delegating administration to a different team.
  • Or you can create different admin profiles for different instances, which allows you to inform the different departments the nsroot password for their VPX instances.

Important: Do not change the password directly on the NetScaler VPX instance. If you do so, the instance becomes unreachable from the Management Service. To change a password, first create a new admin profile, and then modify the NetScaler instance, selecting this profile from the Admin Profile list.

  1. On the Configuration tab, in the navigation pane, expand NetScaler, and then click Admin Profiles.
  2. In the Admin Profiles pane, click Add.
  3. In the Create Admin Profile dialog box, set the following parameters:
    • Profile Name*—Name of the admin profile.
    • User Name—User name used to log on to the NetScaler instances. The user name of the default profile is nsroot and cannot be changed.
    • Password*—The password used to log on to the NetScaler instance. Maximum length: 31 characters.
    • Confirm Password*—The password used to log on to the NetScaler instance.
    • Use global settings for NetScaler communication – you can uncheck this box and change the protocol to https.
  4. Click Create. The admin profile you created appears in the Admin Profiles pane.

Upload a NetScaler VPX .xva file

You must upload a NetScaler VPX .xva file to the SDX appliance before provisioning the NetScaler VPX instances. XVA files are only used when creating a new instance. Once the instance is created, use normal firmware upgrade procedures.

  1. Download the NetScaler XVA (for XenServer) from the SDX Software Bundle Download Page. It’s in the Virtual Appliance section.
  2. After downloading, extract the .gz file (use 7-zip). You can’t upload the .gz file to SVM. You must extract it first.
  3. On the Configuration tab, in the navigation pane, expand NetScaler, and then click Software Images.
  4. On the right, switch to the XVA Files tab, and then click Upload.
  5. In the Upload NetScaler Instance XVA dialog box, click Browse, and select the XVA image file that you want to upload. Click Upload.

  6. The XVA image file appears in the XVA Files pane after it is uploaded.

Provision a NetScaler instance

  1. On the SDX Management Service, go to the Dashboard page.
  2. On the bottom right, the System Resource Utilization pane shows you the amount of physical resources that are available for allocation.
  3. On the Configuration tab, in the navigation pane, expand NetScaler, and then click Instances.
  4. In the NetScaler Instances pane, click Add.
  5. In the Provision NetScaler section, enter a name for the instance.
  6. Enter the NSIP, mask, and Gateway.
  7. Nexthop to Management Service – If the instance’s NSIP is on a different subnet than the SVM IP, and if the instance’s default gateway is on a different network than the NSIP, then enter a next hop router address on the NSIP network, so the instance can respond to the SDX Management Service.
  8. In the XVA File field, you can Browse > Local to select an XVA file on your local machine that hasn’t been uploaded to SDX yet. Or you can Browse > Appliance, and select an XVA file that has already been uploaded to SDX.

  9. Select an Admin Profile created earlier. Or you can click the plus icon to create a new Admin Profile.
  10. Enter a Description. Scroll down.
  11. In the License Allocation section, change the Feature License to Platinum.
  12. For Throughput, partition your licensed bandwidth. If you are licensed for 40 Gbps, make sure the total of all VPX instances does not exceed that number.
  13. For Allocation Mode, Burstable is also an option. Fixed bandwidth can’t be shared with other instances. Burstable can be shared. See Bandwidth Metering in NetScaler SDX at Citrix Docs.
  14. In the Resource Allocation section, consider changing the Total Memory to 4096.
  15. For SSL Chips, specify a number. Some SSL/TLS features require at least one chip.
    • NetScaler SDX 8900 series does not use SSL Chips. Instead, it uses Crypto Units. See Crypto Management at Citrix Docs.
  16. For CPU, for production instances, select one of the Dedicated options. Dev/Test instances can use Shared CPU. Then scroll down.
  17. In the Instance Administration section, you can optionally add an instance administrator. Enter a new local account that will be created on the VPX. This instance admin is in addition to the nsroot user. Note, networking functionality is not available to this account. Scroll down.

  18. In the Network Settings section, leave 0/1 selected, and deselect 0/2.
  19. Click Add to connect the VPX to more interfaces.
  20. If you have Port Channels, select one of the LA interfaces.
  21. If you configure any VLAN settings here, then XenServer filters the VLANs available to the VPX instance. Changing the VLAN filtering settings later probably requires a reboot. Click Add. Note: VLAN tagging is configured inside the instance.
  22. In the Management VLAN Settings section, do not configure anything in this section unless you need to tag the NSIP VLAN.
  23. Click Done.
  24. After a couple minutes the instance will be created. Click Close.

  25. If you go to the Dashboard page…

    1. If you click an instance name, you can see how the instance is connected to the physical NICs.
  26. Back in Configuration > NetScaler > Instances, in your Instances list, click the IP address link to launch the VPX management console. Or, simply point your browser to the NSIP and login.
  27. Do the following at a minimum (instructions are in the NetScaler System Configuration post):
    1. Create Policy Based Route for the NSIP – System > Settings > Network > PBRs
    2. Add SNIPs for each VLAN – System > Network > IPs
    3. Add VLANs and bind to SNIPs – System > Network > VLANs
    4. Create Static Routes for internal networks – System > Network > Routes
    5. Change default gateway – System > Network > Routes > 0.0.0.0
    6. Create another instance on a different SDX, and High Availability pair them together – System > High Availability

VPX Instances – Manage

You may login to the VPX instance and configure everything normally. SDX also offers the ability to manage IP addresses, and SSL certificates, from SDX, rather than from inside the VPX instance. The SDX Management Service does not have the ability to create certificates, so it’s probably best to do that from within the VPX instance.

View the console of a NetScaler instance

  1. Connect to the Management Service using https.
    1. Viewing the virtual machine console might not work unless you install a valid certificate for the Management Service.
  2. In the Management Service, go to Configuration > NetScaler > Instances.
  3. On the right, right-click an instance, and click Console.
  4. The instance console then appears.
  5. Another option is to use the Lights Out Module, and the xl console command, as detailed at Citrix Blog Post SDX Remote Console Access of VIs.

Start, stop, delete, or restart a NetScaler instance

  1. On the Configuration tab, in the navigation pane, expand NetScaler, and click Instances.
  2. On the right, in the Instances pane, right-click the NetScaler instance on which you want to perform the operation, and then click Start or Shut Down or Delete or Reboot.
  3. In the Confirm message box, click Yes.

Create a Subnet IP Address on a NetScaler Instance

  1. On the Configuration tab, in the navigation pane, click NetScaler.
  2. On the right, in the NetScaler Configuration pane, click Create IP.
  3. In the Create NetScaler IP dialog box, specify values for the following parameters.
    • IP Address* – Specify the IP address assigned as the SNIP address.
    • Netmask* – Specify the subnet mask associated with the SNIP address.
    • Type* – Specify the type of IP address. Possible values: SNIP.
    • Save Configuration* – Specify whether the configuration should be saved on the NetScaler. Default value is false.
    • Instance IP Address* – Specify the IP address of the NetScaler instance on which this SNIP will be created.
  4. Click Create.

Create a VLAN on a NetScaler instance

  1. Go to NetScaler > Instances.
  2. On the right, right-click an instance, and click VLAN Bindings.
  3. Click Add.
  4. Enter a VLAN ID, and select an interface.
  5. Check the box for Tagged if needed.
  6. Notice there’s no way to bind a SNIP. You do that inside the instance. Click Create.

Save the configuration of a NetScaler instance

  1. On the Configuration tab, in the navigation pane, click NetScaler.
  2. On the right, in the NetScaler pane, click Save Configuration.
  3. In the Save Configuration dialog box, in Instance IP Address, select the IP addresses of the NetScaler instances whose configuration you want to save.
  4. Click OK.

Change NSIP of VPX Instance

The best way to change the NSIP is to edit the instance.

If you change NSIP inside of VPX instead of Editing the Instance in the Management Service, see article CTX139206 How to Change NSIP of VPX Instance in SDX to adjust the XenServer settings.

Enable Call Home

  1. On the Configuration tab, in the navigation pane, click the NetScaler node.
  2. On the right, click Call Home.
  3. Enter an email address to receive communications regarding NetScaler Call Home.
  4. Check the box next to Enable Call Home.
  5. Click Add.
  6. Select the instances to enable Call Home by moving them to the right, and click OK.
  7. You can view the status of Call Home by expanding NetScaler, and clicking Call Home.
  8. The right pane indicates if it’s enabled or not. You can also configure Call Home from here.

VPX Instance – Firmware Upgrade

Upload NetScaler Firmware Build Files

To upgrade a VPX instance from the Management Service, first upload the firmware build file.

  1. Download the NetScaler firmware using the normal method. It’s in the Build section.
  2. On the SDX, in the Configuration tab, on the left, expand NetScaler, and click Software Images.
  3. On the right, in the Software Images tab, click Upload.
  4. Browse to the build…tgz file, and click Open.

Upgrade Multiple NetScaler VPX Instances

You can upgrade multiple instances at the same time:

  1. To prevent any loss of the configuration running on the instance that you want to upgrade, save the configuration on the instance before you upgrade the instance.
  2. On the Configuration tab, in the navigation pane, expand NetScaler, and click Instances.
  3. Right-click an instance, and click Upgrade.
  4. In the Upgrade NetScaler dialog box, in Build File, select the NetScaler upgrade build file of the version you want to upgrade to. Click OK.

Management Service Monitoring

  1. To view syslog, in the navigation pane, expand System, click Auditing, and then click Syslog Message in the right pane.
  2. To view the task log, in the navigation pane, expand Diagnostics, and then click Task Log.
  3. To view Management Service events, on the Configuration tab, in the expand System and click Events.
  4. NetScaler > Entities lets you see the various Load Balancing entities configured on the instances. You might have to click Poll Now to get them to show up.
  5. To view instance alerts, go to NetScaler > Events > All Events.
  6. There is also event reporting.

Management Service Backups

The SDX appliance automatically keeps three backups of the Management Service configuration that are taken daily at 12:30 am.

Backups in NetScaler SDX contain the following:

  • Single bundle image
  • NetScaler XVA image
  • NetScaler upgrade image
  • Management Service image
  • Management Service configuration
  • NetScaler SDX configuration
  • NetScaler configuration

You can go to Management Service > Backup Files to backup or restore the SDX appliance’s configuration. And you can download the backup files.

You can configure the number of retained backups by clicking System on the left, and then clicking Backup Policy in the right pane.

You can even transfer the backup files to an external system.

VMware Horizon Unified Access Gateway Load Balancing – NetScaler 12

Last Modified: Sep 16, 2017 @ 2:05 pm

Navigation

Use this procedure to load balance VMware Unified Access Gateway (formerly known as Access Point).

Overview

To simplify this post, this post is focused on Unified Access Gateway, which is the replacement for Horizon Security Servers.

For load balancing of other Horizon components:

  • Internal Horizon Connection Servers – This is standard load balancing on SSL_BRIDGE protocol, port 443, and Source IP persistence. See the CLI commands for a sample configuration.
  • Horizon Security Servers – Detailed configuration for Horizon Security Servers have been removed from this version of the post. But the CLI commands for Security Server load balancing are preserved at the bottom of this post.

UAG appliances vs Horizon Security Servers

There are two VMware-provided remote access solutions for Horizon View:

Unified Access Gateway appliances are preferred over Horizon Security Servers for the following reasons:

  • No need to pair with internal Connection Servers, which simplifies the configuration.
  • Linux appliance instead of Windows server.
  • Authentication can be offloaded to the Unified Access Gateway. This includes: Smart Cards, RSA, and RADIUS.
  • Blast Extreme Adaptive Transport (BEAT) in Horizon 7.1 and newer only works with Unified Access Gateway 2.9 and newer. Security Server and older Access Points don’t work.
    • VMware Blog Post Deep Dive into VMware Horizon Blast Extreme Adaptive Transport – Blast Extreme Adaptive Transport is enabled by default in VMware Horizon View 7.1 and Horizon Client 4.4. If the clients are connecting from outside the demilitarized zone (DMZ), you would also need to have VMware Unified Access Gateway (not Security Server) to take full advantage of the new transport. The adaptive transport will automatically sense the network for UDP availability and will fallback to legacy Blast TCP if UDP is not available.  💡

Here is a typical Unified Access Gateway architecture:

  • Two Internal Connection Servers – these need to be load balanced on an internal VIP on TCP 443. Internal users connect to the internal VIP.
    • Instructions for load balancing the internal Connection Servers are not detailed in this post. Instead, see the CLI Commands.
  • Two DMZ Unified Access Gateway (Access Point) appliances – these need to be load balanced on a DMZ VIP on several ports. External users connect to the DMZ VIP.
    • Unified Access Gateway appliances connect to the internal Load Balancing VIP for the internal Connection Servers using HTTPS protocol
    • Unified Access Gateway appliances connect directly to Horizon Agents using Blast or PCoIP protocol.

Protocols/Ports

Horizon 7 introduces a new Blast Extreme protocol. VMware Technical White Paper Blast Extreme Display Protocol in Horizon 7.

For VMware Unified Access Gateway (UAG), Blast Extreme only needs TCP 443, and UDP 443. If you use VMware Unified Access Gateway with Blast Extreme exclusively, then the number of ports to UAG is minimal, and load balancing configuration is simplified. Here are typical load balancing port requirements for Unified Access Gateway with Blast Extreme only:

  • TCP 443
  • UDP 443

Note: UDP is disabled by default, but it can be enabled using a Blast GPO setting.

To support Blast Extreme, PCoIP, and HTML Blast connectivity, the following ports must be load balanced to the UAGs:

  • TCP 443
  • UDP 443
  • TCP 4172
  • UDP 4172
  • TCP 8443
  • UDP 8443

The initial connection to UAG is always TCP 443 (HTTPS). If a user is load balanced on port 443 to a particular UAG, then the connection on UDP 4172 must go the same UAG. Normally load balancing persistence only applies to a single port number, so whatever UAG was selected for port 443, won’t be considered for the 4172 connection. But in NetScaler, you can configure a Persistency Group to use a single persistency across multiple load balancing Virtual Servers with different port numbers. In F5, you configure Match Across.

Also see Load Balancing across VMware Unified Access Gateway Appliances by Mark Benson at VMware Communities.

This topic primarily focuses on NetScaler GUI configuration. Alternatively, you can skip directly to the CLI commands.

Load Balancing Monitors

Users connect to Unified Access Gateway appliances on multiple ports: TCP 443, UDP 443, TCP 8443, UDP 8443, TCP 4172, and UDP 4172. Create Load Balancing Monitors for each port number. Since UDP can’t be easily monitored, use TCP monitors as substitutes for UDP. That means you only need three monitors:

  • TCP 443 – HTTPS
  • TCP 4172
  • TCP 8443

SSL (443) Monitor

  1. On the left, expand Traffic Management, expand Load Balancing, and click Monitors.
  2. On the right, click Add.
  3. Name it Horizon-SSL or similar.
  4. Change the Type drop-down to HTTP-ECV.
  5. On the Standard Parameters tab, in the Destination Port field, enter 443.
  6. Scroll down the Standard Parameters tab, and check the box next to Secure.
  7. Scroll back up, and switch to the Special Parameters tab.
  8. In the Send String section, enter GET /broker/xml
  9. In the Receive String section, enter clientlaunch-default
  10. Scroll down, and click Create.

PCoIP (4172) Monitor

  1. On the right, click Add.
  2. Name it Horizon-PCoIP or similar.
  3. Change the Type drop-down to TCP.
  4. On the Standard Parameters tab, in the Destination Port field, enter 4172.
  5. Scroll down, and click Create.

Blast (8443) Monitor

  1. On the right, click Add.
  2. Name it Horizon-Blast or similar.
  3. Change the Type drop-down to TCP.
  4. On the Standard Parameters tab, in the Destination Port field, enter 8443.
  5. Scroll down, and click Create.

Load Balancing Servers

Create Load Balancing Server Objects for the DMZ Unified Access Gateway appliances.

  1. On the left, expand Traffic Management, expand Load Balancing, and click Servers.
  2. On the right, click Add.
  3. Enter a descriptive server name, usually it matches the actual appliance name.
  4. Enter the IP address of a Unified Access Gateway appliance.
  5. Enter comments to describe the server. Click Create.
  6. Continue adding Unified Access Gateway appliances.

Load Balancing Services

Overview

Since there are six protocol/ports to UAG, there will be six service groups – one for each protocol/port:

  • TCP 443 – SSL_BRIDGE
  • UDP 443
  • UDP 4172
  • TCP 4172
  • TCP 8443 – SSL_BRIDGE
  • UDP 8443

Users will initially connect to TCP port 443, and then must be redirected to one of the other ports on the same UAG appliance that was initially used for the TCP 443 connection. If TCP 443 is up, but UDP 4172 is down on the same appliance, then you probably TCP 443 to go down too. To facilitate this, bind all three port number monitors to the TCP 443 service. If any of the bound monitors goes down, then TCP 443 is also taken down.

  • Only the TCP 443 service group needs to monitor all port numbers.
  • Other port number service groups only need to monitor that specific port number. For example, the TCP 8443 Service Group should monitor port TCP 8443.
  • Since UDP is difficult to monitor, the UDP Service Groups will monitor the equivalent TCP port. For example, the UDP 4172 Service Group will monitor TCP 4172. This isn’t the best option, but it’s better than ping.

TCP 443 Load Balancing Service Group

  1. On the left, expand Traffic Management, expand Load Balancing, and click Service Groups.
  2. On the right, click Add.
  3. Give the Service Group a descriptive name (e.g. svcgrp-UAG-SSL).
  4. Change the Protocol to SSL_BRIDGE, and click OK to close the Basic Settings section.
  5. On the left, click where it says No Service Group Member.

    1. Change the selection to Existing Server, and select the Unified Access Gateway appliances you created earlier.

    2. In the Port field, enter 443, and click Create.
  6. Click OK to close the Service Group Members section.
  7. On the right, in the Advanced Settings column, click Monitors.
  8. On the left, in the Monitors section, click where it says No Service Group to Monitor Binding.

    1. Click where it says Click to select.
    2. Click the radio button next to the Horizon-SSL monitor, and click Select.
    3. Click Bind.
  9. The TCP 443 Service Group should monitor all port numbers. To bind more monitors, on the left, click where it says 1 Service Group to Monitor Binding.

    1. Click Add Binding.
    2. Click where it says Click to select.
    3. Click the radio button next to the Horizon-PCoIP monitor, and click Select.
    4. Then click Bind.
    5. Repeat these steps to bind the Horizon-Blast monitor. If any of these monitors goes down, then the UAG is taken offline.
    6. Click Close.
  10. To verify the monitors, on the left, in the Service Group Members section, click the line that says # Service Group Members.

    1. Right-click one of the members, and click Monitor Details.
    2. The Last Response should indicate Success. If you bound multiple monitors to the Service, then the member will only be UP if all monitors succeed.
    3. Click Close when done.
  11. Then click Done to finish creating the Service Group.

Other Ports Load Balancing Services

Here are general instructions for the other Horizon UAG load balancing service groups.

  1. On the left, go to Traffic Management > Load Balancing > Service Groups.
  2. On the right, click Add.
  3. Name it svcgrp-Horizon-UDP443 or similar.
  4. Change the Protocol to UDP. Click OK.
  5. Click where it says No Service Group Member.

    1. Change the selection to Server Based, and then click Click to select.
    2. Select your multiple Unified Access Gateway appliances, and click Select.
    3. Enter 443 as the Port. Click Create.
  6. Click OK to close the Service Group Members section.
  7. On the right, in the Advanced Settings column, add the Monitors section.

    1. On the left, in the Monitors section, click where it says No Service Group to Monitor Binding.
    2. Click where it says Click to select.
    3. Select the Horizon-SSL monitor, click Select, and then click Bind.
  8. Click Done to finish creating the Service Group for UDP 443.
  9. Add another Service Group for PCoIP on TCP 4172.
    1. Name = svcgrp-Horizon-PCoIPTCP or similar.
    2. Protocol = TCP
    3. Members = multiple Unified Access Gateway appliances.
    4. Port = 4172.
    5. Monitors = Horizon-PCoIP. You can add the other monitors if desired.
  10. Add another Service Group for PCoIP on UDP 4172.
    1. Name = svcgrp-Horizon-PCoIPUDP or similar.
    2. Protocol = UDP
    3. Members = multiple Unified Access Gateway appliances
    4. Port = 4172.
    5. Monitors = Horizon-PCoIP. You can add the other monitors if desired.
  11. Add another Service Group for SSL_BRIDGE 8443.
    1. Name = svcgrp-Horizon-TCP8443 or similar.
    2. Protocol = SSL_BRIDGE
    3. Members = multiple Unified Access Gateway appliances
    4. Port = 8443.
    5. Monitors = Horizon-Blast. You can add the other monitors if desired.
  12. Add another Service Group for UDP 8443 (Blast Extreme in Horizon 7).
    1. Name = svcgrp-Horizon-UDP8443 or similar.
    2. Protocol = UDP
    3. Members = multiple Unified Access Gateway appliances
    4. Port = 8443.
    5. Monitors = Horizon-Blast. You can add the other monitors if desired.
  13. The six service groups should look something like this:

Load Balancing Virtual Servers

Unified Access Gateway appliances listen on multiple ports so you will need separate load balancers for each port number. Here is a summary of their Virtual Servers, all listening on the same Virtual IP address:

  • Virtual Server on SSL_BRIDGE 443 – bind the SSL_BRIDGE 443 service group.
  • Virtual Server on UDP 443 (Horizon 7) – bind the UDP 443 service group.
  • Virtual Server on UDP 4172 – bind the PCoIP UDP service group.
  • Virtual Server on TCP 4172 – bind the PCoIP TCP service group.
  • Virtual Server on SSL_BRIDGE 8443 – bind the SSL_BRIDGE 8443 service group.
  • Virtual Server on UDP 8443 (Horizon 7) – bind the UDP 8443 service group.

Do the following to create the Virtual Servers:

  1. On the left, under Traffic Management > Load Balancing, click Virtual Servers.
  2. On the right, click Add.
  3. In the Basic Settings section:
    1. Name it lbvip-Horizon-SSL or similar.
    2. Change the Protocol to SSL_BRIDGE.
    3. Specify a new VIP. This one VIP will be used for all of the Virtual Servers.
    4. Enter 443 as the Port.
  4. Click OK to close the Basic Settings section.
  5. On the left, in the Services and Service Groups section, click where it says No Load Balancing Virtual Server ServiceGroup Binding.

    1. Click where it says Click to select.
    2. Click the radio button next to the Horizon-SSL Service Group, and click Select.
    3. Click Bind.
  6. Click Continue to close the Services and Service Groups section.
  7. Then click Done to finish creating the Load Balancing Virtual Server. Persistency will be configured later.
  8. Create another Load Balancing Virtual Server for UDP 443. You can right-click the existing Load Balancing Virtual Server, and click Add to copy some settings.

    1. Same VIP as the TCP 443 Load Balancer.
    2. Protocol = UDP, Port = 443
    3. Service Group Binding = the UDP 443 Service Group

  9. Create another Load Balancing Virtual Server for PCoIP UDP 4172:
    1. Same VIP as the 443 Load Balancer.
    2. Protocol = UDP, Port = 4172
    3. Service Group Binding = the PCoIP UDP Service Group.

  10. Create another Load Balancing Virtual Server for PCoIP TCP 4172:
    1. Same VIP as the 443 Load Balancer.
    2. Protocol = TCP, Port = 4172
    3. Service Group Binding = the PCoIP TCP Service Group

  11. Create another Load Balancing Virtual Server for SSL_BRIDGE 8443:
    1. Same VIP as the 443 Load Balancer.
    2. Protocol = SSL_BRIDGE, Port = 8443
    3. Service Group Binding = the TCP 8443 SSL_BRIDGE Service Group

  12. Ceate another Load Balancing Virtual Server for UDP 8443:
    1. Same VIP as the 443 Load Balancer.
    2. Protocol = UDP, Port = 8443
    3. Service Group Binding = the UDP 8443 Service Group

  13. This gives you six Virtual Servers on the same VIP, but different protocols and port numbers.

Persistency Group

Users will first connect to SSL_BRIDGE 443, and be load balanced. Subsequent connections to the other port numbers must go to the same load balanced appliance. Create a Persistency Group to facilitate this.

  1. On the left, under Traffic Management, expand Load Balancing, and click Persistency Groups.
  2. On the right, click Add.
  3. Give the Persistency Group a name (e.g. Horizon).
  4. Change the Persistence drop-down to SOURCEIP.
  5. Enter a Time-out that is equal to, or greater than the timeout in Horizon View Administrator, which defaults to 10 hours (600 minutes).
  6. In the Virtual Server Name section, click Add.
  7. Move all six Unified Access Gateway Load Balancing Virtual Servers to the right. Click Create.

Horizon 7 Origin Check

Origin Check might prevent you from connecting to load balanced Connection Servers and/or Unified Access Gateways. You can disable Origin Check as detailed at VMware 2144768 Accessing the Horizon View Administrator page displays a blank error window in Horizon 7.

Load Balancing CLI Commands

Internal Connection Server Load Balancing

add server VCS01 10.2.2.19
add server VCS02 10.2.2.20
add serviceGroup svcgrp-VCS-SSL SSL_BRIDGE
add lb vserver lbvip-Horizon-SSL SSL_BRIDGE 10.2.5.203 443 -persistenceType SOURCEIP -timeout 600
bind lb vserver lbvip-Horizon-SSL svcgrp-VCS-SSL
add lb monitor Horizon-SSL HTTP-ECV -send "GET /broker/xml" -recv clientlaunch-default -LRTM DISABLED -destPort 443 -secure YES
bind serviceGroup svcgrp-VCS-SSL VCS01 443
bind serviceGroup svcgrp-VCS-SSL VCS02 443
bind serviceGroup svcgrp-VCS-SSL -monitorName Horizon-SSL

Unified Access Gateway load balancing with Blast Extreme only (no PCoIP)

add server UAG01 10.2.2.187
add server UAG02 10.2.2.24
add lb monitor Horizon-SSL HTTP-ECV -send "GET /broker/xml" -recv clientlaunch-default -secure YES
add serviceGroup svcgrp-Horizon-SSL SSL_BRIDGE
add serviceGroup svcgrp-Horizon-UDP443 UDP
bind serviceGroup svcgrp-Horizon-SSL UAG01 443
bind serviceGroup svcgrp-Horizon-SSL UAG02 443
bind serviceGroup svcgrp-Horizon-SSL -monitorName Horizon-SSL
bind serviceGroup svcgrp-Horizon-UDP443 UAG01 443
bind serviceGroup svcgrp-Horizon-UDP443 UAG02 443
bind serviceGroup svcgrp-Horizon-UDP443 -monitorName Horizon-SSL
add lb vserver lbvip-Horizon-SSL SSL_BRIDGE 10.2.2.204 443
add lb vserver lbvip-Horizon-UDP443 UDP 10.2.2.204 443
bind lb vserver lbvip-Horizon-SSL svcgrp-Horizon-SSL
bind lb vserver lbvip-Horizon-UDP443 svcgrp-Horizon-UDP443
bind lb group Horizon lbvip-Horizon-SSL
bind lb group Horizon lbvip-Horizon-UDP443
set lb group Horizon -persistenceType SOURCEIP -timeout 600

Unified Access Gateway load balancing with Blast and PCoIP

add server UAG01 10.2.2.187
add server UAG02 10.2.2.188
add serviceGroup svcgrp-UAG-SSL SSL_BRIDGE
add serviceGroup svcgrp-UAG-UDP443 UDP
add serviceGroup svcgrp-UAG-PCoIPTCP TCP
add serviceGroup svcgrp-UAG-PCoIPUDP UDP
add serviceGroup svcgrp-UAG-TCP8443 SSL_BRIDGE
add serviceGroup svcgrp-UAG-UDP8443 UDP
add lb vserver lbvip-Horizon-SSL SSL_BRIDGE 10.2.5.204 443
add lb vserver lbvip-Horizon-UDP443 UDP 10.2.5.204 443
add lb vserver lbvip-Horizon-PCoIPUDP UDP 10.2.5.204 4172
add lb vserver lbvip-Horizon-PCoIPTCP TCP 10.2.5.204 4172
add lb vserver lbvip-Horizon-8443SSL SSL_BRIDGE 10.2.5.204 8443
add lb vserver lbvip-Horizon-8443UDP UDP 10.2.5.204 8443
bind lb vserver lbvip-Horizon-SSL svcgrp-UAG-SSL
bind lb vserver lbvip-Horizon-UDP443 svcgrp-UAG-UDP443
bind lb vserver lbvip-Horizon-PCoIPTCP svcgrp-UAG-PCoIPTCP
bind lb vserver lbvip-Horizon-PCoIPUDP svcgrp-UAG-PCoIPUDP
bind lb vserver lbvip-Horizon-8443SSL svcgrp-UAG-TCP8443
bind lb vserver lbvip-Horizon-8443UDP svcgrp-UAG-UDP8443
add lb group Horizon -persistenceType SOURCEIP -timeout 600
bind lb group Horizon lbvip-Horizon-SSL
bind lb group Horizon lbvip-Horizon-UDP443
bind lb group Horizon lbvip-Horizon-PCoIPUDP
bind lb group Horizon lbvip-Horizon-PCoIPTCP
bind lb group Horizon lbvip-Horizon-8443SSL
bind lb group Horizon lbvip-Horizon-8443UDP
set lb group Horizon -persistenceType SOURCEIP -timeout 600
add lb monitor Horizon-SSL HTTP-ECV -send "GET /broker/xml" -recv clientlaunch-default -LRTM DISABLED -destPort 443 -secure YES
add lb monitor Horizon-PCoIP TCP -LRTM DISABLED -destPort 4172 -secure YES
add lb monitor Horizon-Blast TCP -LRTM DISABLED -destPort 8443 -secure YES
bind serviceGroup svcgrp-UAG-SSL UAG01 443
bind serviceGroup svcgrp-UAG-SSL UAG02 443
bind serviceGroup svcgrp-UAG-SSL -monitorName Horizon-SSL
bind serviceGroup svcgrp-UAG-SSL -monitorName Horizon-PCoIP
bind serviceGroup svcgrp-UAG-SSL -monitorName Horizon-Blast
bind serviceGroup svcgrp-UAG-UDP443 UAG01 443
bind serviceGroup svcgrp-UAG-UDP443 UAG02 443
bind serviceGroup svcgrp-UAG-UDP443 -monitorName Horizon-SSL
bind serviceGroup svcgrp-UAG-PCoIPTCP UAG01 4172
bind serviceGroup svcgrp-UAG-PCoIPTCP UAG02 4172
bind serviceGroup svcgrp-UAG-PCoIPTCP -monitorName Horizon-PCoIP
bind serviceGroup svcgrp-UAG-PCoIPUDP UAG01 4172
bind serviceGroup svcgrp-UAG-PCoIPUDP UAG02 4172
bind serviceGroup svcgrp-UAG-PCoIPUDP -monitorName Horizon-PCoIP
bind serviceGroup svcgrp-UAG-TCP8443 UAG01 8443
bind serviceGroup svcgrp-UAG-TCP8443 UAG02 8443
bind serviceGroup svcgrp-UAG-TCP8443 -monitorName Horizon-Blast
bind serviceGroup svcgrp-UAG-UDP8443 UAG01 8443
bind serviceGroup svcgrp-UAG-UDP8443 UAG02 8443
bind serviceGroup svcgrp-UAG-UDP8443 -monitorName Horizon-Blast

Horizon Security Server load balancing

add server VSS01 10.2.2.187
add server VSS02 10.2.2.24
add lb monitor Horizon-PCoIP TCP -destPort 4172
add lb monitor Horizon-Blast TCP -destPort 8443
add lb monitor Horizon-SSL HTTP-ECV -send "GET /broker/xml" -recv clientlaunch-default -secure YES
add lb monitor Horizon-SSL-VCS01 HTTP-ECV -send "GET /broker/xml" -recv clientlaunch-default -destIP 10.2.2.19 -destPort 443 -secure YES
add lb monitor Horizon-SSL-VCS02 HTTP-ECV -send "GET /broker/xml" -recv clientlaunch-default -destIP 10.2.2.20 -destPort 443 -secure YES
add service svc-VSS01-SSL VSS01 SSL_BRIDGE 443
add service svc-VSS02-SSL VSS02 SSL_BRIDGE 443
bind service svc-VSS02-SSL -monitorName Horizon-SSL-VCS02
bind service svc-VSS02-SSL -monitorName Horizon-SSL
bind service svc-VSS02-SSL -monitorName Horizon-Blast
bind service svc-VSS02-SSL -monitorName Horizon-PCoIP
bind service svc-VSS01-SSL -monitorName Horizon-SSL-VCS01
bind service svc-VSS01-SSL -monitorName Horizon-Blast
bind service svc-VSS01-SSL -monitorName Horizon-PCoIP
bind service svc-VSS01-SSL -monitorName Horizon-SSL
add serviceGroup svcgrp-Horizon-UDP443 UDP
add serviceGroup svcgrp-Horizon-PCoIPTCP TCP
add serviceGroup svcgrp-Horizon-PCoIPUDP UDP
add serviceGroup svcgrp-Horizon-TCP8443 SSL_BRIDGE
add serviceGroup svcgrp-Horizon-UDP8443 UDP
bind serviceGroup svcgrp-Horizon-UDP443 VSS01 443
bind serviceGroup svcgrp-Horizon-UDP443 VSS02 443
bind serviceGroup svcgrp-Horizon-UDP443 -monitorName Horizon-SSL
bind serviceGroup svcgrp-Horizon-PCoIPTCP VSS01 4172
bind serviceGroup svcgrp-Horizon-PCoIPTCP VSS02 4172
bind serviceGroup svcgrp-Horizon-PCoIPTCP -monitorName Horizon-PCoIP
bind serviceGroup svcgrp-Horizon-PCoIPUDP VSS01 4172
bind serviceGroup svcgrp-Horizon-PCoIPUDP VSS02 4172
bind serviceGroup svcgrp-Horizon-PCoIPUDP -monitorName Horizon-PCoIP
bind serviceGroup svcgrp-Horizon-TCP8443 VSS01 8443
bind serviceGroup svcgrp-Horizon-TCP8443 VSS02 8443
bind serviceGroup svcgrp-Horizon-TCP8443 -monitorName Horizon-Blast
bind serviceGroup svcgrp-Horizon-UDP8443 VSS01 8443
bind serviceGroup svcgrp-Horizon-UDP8443 VSS02 8443
bind serviceGroup svcgrp-Horizon-UDP8443 -monitorName Horizon-Blast
add lb vserver lbvip-Horizon-SSL SSL_BRIDGE 10.2.2.204 443
add lb vserver lbvip-Horizon-UDP443 UDP 10.2.2.204 443
add lb vserver lbvip-Horizon-PCoIPUDP UDP 10.2.2.204 4172
add lb vserver lbvip-Horizon-PCoIPTCP TCP 10.2.2.204 1472
add lb vserver lbvip-Horizon-8443TCP SSL_BRIDGE 10.2.2.204 8443
add lb vserver lbvip-Horizon-8443UDP UDP 10.2.2.204 8443
bind lb vserver lbvip-Horizon-SSL svc-VSS01-SSL
bind lb vserver lbvip-Horizon-SSL svc-VSS02-SSL
bind lb vserver lbvip-Horizon-UDP443 svcgrp-Horizon-UDP443
bind lb vserver lbvip-Horizon-PCoIPTCP svcgrp-Horizon-PCoIPTCP
bind lb vserver lbvip-Horizon-PCoIPUDP svcgrp-Horizon-PCoIPUDP
bind lb vserver lbvip-Horizon-8443TCP svcgrp-Horizon-TCP8443
bind lb vserver lbvip-Horizon-8443UDP svcgrp-Horizon-UDP8443
bind lb group Horizon lbvip-Horizon-SSL
bind lb group Horizon lbvip-Horizon-UDP443
bind lb group Horizon lbvip-Horizon-PCoIPUDP
bind lb group Horizon lbvip-Horizon-PCoIPTCP
bind lb group Horizon lbvip-Horizon-8443TCP
bind lb group Horizon lbvip-Horizon-8443UDP
set lb group Horizon -persistenceType SOURCEIP -timeout 600

Citrix Director Load Balancing – NetScaler 12

Last Modified: Aug 29, 2017 @ 3:47 pm

Navigation

Monitor

  1. On the left, expand Traffic Management, expand Load Balancing, and click Monitors.
  2. On the right, click Add.
  3. Name it Director or similar.
  4. Change the Type drop-down to HTTP.
  5. If you will use SSL to communicate with the Director servers, then on the Standard Parameters tab, scroll down, and check the box next to Secure.
  6. Scroll up, and switch to the Special Parameters tab.
  7. In the HTTP Request field, enter GET /Director/LogOn.aspx?cc=true
    1. If Single Sign-on is enabled on Director, then you might have to add 302 as a Response Code.
  8. Scroll down, and click Create.

Servers

  1. On the left, expand Traffic Management, expand Load Balancing, and click Servers.
  2. On the right, click Add.
  3. Enter a descriptive server name. Usually it matches the actual server name.
  4. Enter the IP address of the Director server.
  5. Enter comments to describe the server. Click Create.
  6. Continue adding Director servers.

Service Group

  1. On the left, expand Traffic Management, expand Load Balancing, and click Service Groups.
  2. On the right, click Add.
  3. Give the Service Group a descriptive name (e.g. svcgrp-Director-SSL).
  4. Change the Protocol to HTTP or SSL, depending on if IIS on the Director server is enabled for https or not.
    1. . If the protocol is SSL, ensure the Monitor for Director has Secure enabled, as detailed earlier.
  5. Scroll down, and click OK.

  6. Click where it says No Service Group Member.

    1. Change the selection to Server Based, and select the Director server objects.

    2. Enter 80 or 443 as the port. Then click Create.
  7. Click OK to close the Service Group Members section.
  8. On the right, under Advanced Settings, click Monitors.
  9. On the left, in the Monitors section, click where it says No Service Group to Monitor Binding.

    1. Click where it says to Click to select.
    2. Click the radio button next to the Director monitor, and click Select.
    3. Then click Bind.
  10. To verify that the monitor is working, on the left, in the Service Group Members section, click the Service Group Members line.
  11. Right-click a member, and click Monitor Details.
  12. The Last Response should be Success – HTTP response code 200 received. Click Close twice.
  13. Then click Done.

Responder

Create a Responder policy to redirect users from the root page to /Director.

  1. Go to AppExpert > Responder, and enable the feature if it isn’t already enabled.
  2. Go to AppExpert > Responder > Actions.
  3. On the right, click Add.

    1. Give the Action a name (e.g. Director_Redirect).
    2. Change the Type to Redirect.
    3. In the Expression box, enter "/Director", including the quotes.
  4. Click Create.
  5. Go to AppExpert > Responder > Policies.
  6. On the right, click Add.

    1. Give the Policy a name (e.g. Director_Redirect).
    2. Select the previously created Action.
    3. In the Expression box, enter HTTP.REQ.URL.PATH.EQ("/")
  7. Click Create.

Load Balancing Virtual Server

  1. Create or install a certificate that will be used by the SSL Virtual Server. This certificate must match the DNS name for the load balanced Director servers.
  2. On the left, under Traffic Management > Load Balancing, click Virtual Servers.
  3. On the right, click Add.
  4. Do the following in the Basic Settings section:
    1. Name it lbvip-Director-SSL or similar.
    2. Change the Protocol to SSL.
    3. Specify a new internal VIP.
    4. Enter 443 as the Port.
  5. Click OK to close the Basic Settings section.
  6. On the left, in the Services and Service section, click where it says No Load Balancing Virtual Server ServiceGroup Binding.

    1. Click where it says Click to select.
    2. Click the radio button next to your Director Service Group, and click Select.
    3. Click Bind.
  7. Click Continue to close the Services and Service Groups section.
  8. Click where it says No Server Certificate.

    1. Click where it says Click to select.
    2. Click the radio button next to the certificate for this Director Load Balancing Virtual Server, and click Select.
    3. Click Bind.
  9. Click Continue to close the Certificate section.
  10. On the right, in the Advanced Settings column, click Persistence.
  11. On the left, in the Persistence section, do the following:
    1. Change the Persistence drop-down to COOKIEINSERT.
    2. Set the Time-out to 0 minutes. This makes it a session cookie instead of a persistent cookie.
    3. Set the Backup Persistence to SOURCEIP.
    4. Set the Backup Time-out to match the timeout of Director. The default timeout for Director is 245 minutes.
    5. The IPv4 Netmask should default to 32 bits.
  12. Click OK.
  13. On the right, in the Advanced Settings section, add the Policies section.
  14. On the left, in the Policies section, click the plus icon.

    1. Change the Choose Policy drop-down to Responder, and click Continue.
    2. Select the previously created Director_Redirect policy, and click Bind.
  15. If you haven’t enabled the Default SSL Profile, then perform other normal SSL configuration including: disable SSLv3, bind a Modern A+ Cipher Group, and enable Strict Transport Security.

SSL Redirect

Do one of the following to configure a redirect from HTTP to HTTPS:

SSL Warning

  1. If you are doing SSL Offload (SSL on front end, HTTP on back end), when connecting to Director, it might complain about “You are not using a secure connection”.
  2. To turn off this warning, login to the Director servers, and run IIS Manager.
  3. On the left, navigate to Server > Sites > Default Web Site > Director.
  4. In the middle, double-click Application Settings.
  5. Change UI.EnableSslCheck to false.

CLI Commands

Here is a list of NetScaler CLI commands for Director Load Balancing:

add server Director01 10.2.2.18
add server Director02 10.2.2.100
add server 127.0.0.1 127.0.0.1
add service AlwaysUp 127.0.0.1 HTTP 80
add serviceGroup svcgrp-Director-HTTP HTTP
add ssl certKey wildcom -cert WildcardCorpCom_pem -key WildcardCorpCom_pem
add lb vserver lbvip-Director-SSL SSL 10.2.2.210 443 -persistenceType SOURCEIP -timeout 245
add lb vserver lbvip-Director-HTTP-SSLRedirect HTTP 10.2.2.210 80 -persistenceType NONE
add responder action Director_Redirect redirect "\"/Director\"" -responseStatusCode 302
add responder action http_to_ssl_redirect_responderact redirect "\"https://\" + HTTP.REQ.HOSTNAME.HTTP_URL_SAFE + HTTP.REQ.URL.PATH_AND_QUERY.HTTP_URL_SAFE" -responseStatusCode 302
add responder policy Director_Redirect "http.REQ.URL.PATH.EQ(\"/\")" Director_Redirect
add responder policy http_to_ssl_redirect_responderpol HTTP.REQ.IS_VALID http_to_ssl_redirect_responderact
bind lb vserver lbvip-Director-HTTP-SSLRedirect AlwaysUp
bind lb vserver lbvip-Director-SSL svcgrp-Director-SSL
bind lb vserver lbvip-Director-SSL -policyName Director_Redirect -priority 100 -gotoPriorityExpression END -type REQUEST
bind lb vserver lbvip-Director-HTTP-SSLRedirect -policyName http_to_ssl_redirect_responderpol -priority 100 -gotoPriorityExpression END -type REQUEST
add lb monitor Director HTTP -respCode 200 -httpRequest "GET /Director/LogOn.aspx?cc=true" -LRTM DISABLED -secure YES
bind serviceGroup svcgrp-Director-SSL Director01 443
bind serviceGroup svcgrp-Director-SSL Director02 443
bind serviceGroup svcgrp-Director-SSL -monitorName Director
set ssl serviceGroup svcgrp-Director-SSL -tls11 DISABLED -tls12 DISABLED
bind ssl vserver lbvip-Director-SSL -certkeyName wildcom
bind ssl vserver lbvip-Director-SSL -eccCurveName P_256
bind ssl vserver lbvip-Director-SSL -eccCurveName P_384
bind ssl vserver lbvip-Director-SSL -eccCurveName P_224
bind ssl vserver lbvip-Director-SSL -eccCurveName P_521

NetScaler Gateway 12 – SSL VPN

Last Modified: Aug 29, 2017 @ 2:41 pm

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Overview

Here’s an overview of the NetScaler Gateway connection process:

  1. Users use SSL/TLS to connect to a NetScaler Gateway Virtual Server (VIP).
  2. NetScaler Gateway prompts the user for authentication.
  3. Once the user is authenticated, NetScaler Gateway uses Session Policies/Profiles to determine what happens next.

NetScaler Gateway 12 supports six different connection methods:

  • ICA Proxy to XenApp/XenDesktop and StoreFront – the client is built into Citrix Receiver
  • SSL VPN – requires installation of NetScaler Gateway plug-in (VPN client)
  • Clientless – browser only, no VPN client, uses rewrite
  • Secure Browse – from MDX-wrapped mobile applications (XenMobile), uses rewrite
  • RDP Proxy – only RDP client is needed
  • PCoIP Proxy – only VMware Horizon Client is needed

You can configure NetScaler Gateway Session Policies/Profiles to only use one of the connection methods. Or NetScaler Gateway can be configured to let users choose between ICA Proxy, Clientless, and SSL VPN connection methods. Here’s a sample Client Choices screen using the RfWebUI theme:

  • The Clientless Access option opens a portal page that has icons from Citrix StoreFront (ICA Proxy), icons for RDP Proxy, icons for PCoIP Proxy, and links to websites.
    • The website links can be proxied through NetScaler. Proxy methods include: clientless rewrite, SSL VPN, and traditional load balancing.
    • NetScaler Gateway can optionally Single Sign-on to the websites.
  •  The Virtual App and Desktop Access option only displays icons from Citrix StoreFront (ICA Proxy). For other types of icons, you’ll need Clientless Access.
  • The Connect with NetScaler Gateway Plug-in option launches the VPN tunnel. After the tunnel is established, a portal page is displayed. This can be the Clientless Access portal, or a user defined website URL (e.g. intranet).

Session Policies/Profiles have several settings that control the behavior seen after authentication:

  • ICA Proxy – ON or OFF
    • If ON, then ICA Proxy is the only connection method allowed, overriding the other connection methods.
    • ICA Proxy does not launch the VPN client. It only needs Citrix Receiver.
    • ICA Proxy shows the Webpage that’s configured in the Web Interface Address field of the Session Profile. This is typically the StoreFront Receiver for Web page, but technically it can be any internal website.
    • If OFF, that doesn’t mean ICA Proxy doesn’t work. You can still send ICA traffic to the NetScaler Gateway Virtual Server, and the NetScaler Gateway Virtual Server will still proxy it to internal VDAs.
    • Setting it to OFF allows the other connection methods to function. For example, Clientless Access can show both NetScaler Gateway Bookmarks and StoreFront published apps. If VPN is launched, then the portal page shown to the user after the tunnel is established can contain the StoreFront published applications.
  • Clientless Access – On, Off, Disabled
    • If On, then Clientless is the only connection method allowed, assuming ICA Proxy is not set to ON. After the user logs in, the user is presented with a portal page that contains a list of Gateway bookmarks and/or StoreFront published icons. The VPN Client is not launched.
    • The Home Page setting in the Session Profile allows you to display an internal website instead of displaying the NetScaler Gateway Portal Page.
    • Bookmarks are configured at NetScaler Gateway > Resources > Bookmarks. You can bind the Bookmarks (Urls) to the NetScaler Gateway Virtual Server, or to AAA Groups.
    • Only Bookmarks configured for Clientless Access will work without a VPN. The internal websites are rewritten so they are proxied through NetScaler Gateway. For example, if the internal website is http://intranet.corp.local, then Gateway rewrites them to https://gateway.corp.com/cvpn/http/internal.corp.local. This causes the web browser to send the HTTP Request to NetScaler Gateway, which then forwards the HTTP Request to the internal web server. No VPN needed.
  • Plug-in Type – Windows/MAC OS X
    • If both Clientless and ICA Proxy are set to Off, then the VPN Client will be downloaded and launched.
    • Once the VPN tunnel is established, the webpage configured in the Home Page setting is displayed. Or the NetScaler Gateway Portal Page (Clientless Access) is displayed if no Home Page is configured. The Bookmarks in the Portal Page can link to internal websites that are only accessible through a VPN tunnel. Or Bookmarks can be configured for Clientless Access.
    • Additional Gateway objects control VPN behavior including: DNS Suffix, Intranet Applications, Intranet IPs, and Authorization Policies.
  • Client Choices – checked or unchecked
    • If Client Choices is checked, then it displays a page containing up to three buttons allowing the user to choose between VPN, Clientless, or StoreFront. The Network Access with the NetScaler Gateway Plug-in (VPN) button is always displayed. The Clientless Access button is displayed if Clientless Access is set to On or Off (not Disabled). The Virtual App and Desktop Access button is displayed if a Web Interface Address is configured.

Here are some characteristics of Session Policies:

  • NetScaler Gateway > Global Settings > Change Global Settings has the same settings as a Session Profile. However, all Session Policies/Profiles override the settings configured in Global Settings. That’s the whole point of the Override Global checkboxes in the Session Profiles.
  • Session Policy Expression – If the Session Policy Expression is true, then the settings contained in the Session Profile are applied.
    • Action = Session Profile – The Session Profile is also sometimes called the Action. That’s because all NetScaler policies follow a standard structure – if the expression evaluates to True, then perform the Action. For Session Policies in particular, the policy Action = Session Profile.
    • EPA – The Session Policy Expression in Classic Syntax could include an Endpoint Analysis (EPA) expression.
  • Default Syntax Expressions vs Classic Syntax Policy Expressions – NetScaler 12 supports Default (Advanced) Syntax Expressions on Session Policies, in addition to the older Classic Syntax.
    • No syntax mixing – All Session Policies bound anywhere must be either Default or Classic. You cannot mix the two types.
    • EPA is Classic only – EPA Scans are only supported in Classic Expressions.
    • AD Group in Default Syntax – Default Syntax allows expressions for AD Group Membership like HTTP.REQ.USER.IS_MEMBER_OF("MyADGroup"). This could eliminate AAA Groups in some circumstances.
  • Policy Bind Points – Session Policies can be bound to three different bind points – NetScaler Gateway Virtual Server, AAA Groups, and AAA User.
    • When bound to a NetScaler Gateway Virtual Server, the Session policy/profile applies to all users that log into that Virtual Server.
    • When bound to a AAA Group, the Session policy/profile only applies to members of the AAA group (Active Directory group or local group)
    • When bound to a AAA User, the Session policy/profile only applies to the AAA user (Active Directory user or local user)
  • Profile Conflicts – Multiple Session Policies/Profiles could apply to a single session. In this case, the Profile settings are merged. But if there’s a conflict (e.g. one Session Profile enables Clientless access, but another Session Profile disables Clientless access), then which one wins?
    • Priority number – When you bind a Session Policy to a bind point, you specify a priority number. This priority number usually defaults to 100.
    • Lowest priority number wins – The Session Policy binding that has the lowest priority number, wins. Session Policies bound with a priority of 80 will win over Session Policies bound with a priority of 100. Remember, for settings that don’t conflict, the two Profiles merge, but for settings that do conflict, the lower priority number policy/profile settings win.
    • Priority and multiple bind points – the bind point location doesn’t matter. If you bind a Session Policy to a AAA Group with a priority of 100, and you also bind a Session Policy to the NetScaler Gateway Virtual Server with a priority of 80, then the conflicting settings in the Session Policy bound to the NetScaler Gateway Virtual Server will win because it has the lower priority number. You might think that AAA-bound policies always override Virtual Server-bound policies, but that is not the case.
  • Global Settings vs Virtual Server Settings – When you bind a Session Policy to a NetScaler Gateway Virtual Server, the settings in the Session Profile only apply to connections through that particular NetScaler Gateway Virtual Server.
    • Settings in NetScaler Gateway > Global Settings > Change Global Settings apply to every Gateway Virtual Server.
    • Settings in AAA Group > Policies > Session Policy/Profile apply to every Gateway Virtual Server.
    • If you want a particular Gateway Virtual Server to override AAA or Global, your only choice is to bind a Session Policy to the Gateway Virtual Server with a lower priority number than the AAA Bind Points.

AAA Groups are a critical component of NetScaler Gateway VPN configuration:

  • Group extraction – Make sure the LDAP Policy/Server is configured to extract to the user’s Active Directory Groups.
  • Create AAA Groups on the NetScaler that match exactly (case sensitive) with the user’s Active Directory Group Name.
    • Default Syntax and AD Groups – An alternative to AAA Groups is to use HTTP.REQ.USER.IS_MEMBER_OF("MyADGroup") Default Syntax expressions. However, Default Syntax does not support Endpoint Analysis. And Default Syntax only applies to Session Policies and Authorization Policies, so you might still need AAA Groups for Bookmarks, Intranet Applications, and Intranet IPs.
  • You can bind policies and other Gateway objects to the AAA Group, and these bindings only affect that particular AAA Group. These bindings include:
  • If the user belongs to multiple AAA Groups, then policies are applied as follows:
    • Session Policies – the settings are merged, unless there’s a conflict. If a conflict, then the policy with the lowest priority number wins.
    • Bookmarks, Intranet Applications, and Authorization Policies are merged.
    • Intranet IPs (IP Pool) are probably random allocation. It’s probably best to make sure a user only belongs to one AAA Group that assigns Intranet IPs.
  • You can also create local AAA Groups that are unrelated to Active Directory groups. There are several ways of getting users into these local AAA groups:
    • Create local AAA Users and assign them to the AAA Group
    • Configure Session Policy/Profile with a Client Security Check String (EPA Scan). If the scan succeeds, users are placed into local Authorization AAA Groups. If the scan fails, then users are placed into a local Quarantine AAA Group, and removed from all other AAA Groups.
    • When users are authenticated with a particular authentication server, the authentication server can be configured to place users into a Default Authentication Group. This lets you apply different Session Policy/Profiles (and other Gateway objects) depending on how the user authenticated.

NetScaler Gateway supports Client Security Expressions (Endpoint Analysis expressions) at three different locations:

  • Preauthentication Policy Expression
    • If the EPA Scan succeeds, then the user is allowed to login.
    • If the EPA Scan fails, then the user is not allowed to login.
    • Preauthentication Policies are bound to NetScaler Gateway Virtual Servers only, and thus applies to all users of that Virtual Server.
  • Session Policy Expression
    • This type of EPA Scan is configured in the Session Policy Expression, not the Session Profile.
    • If the EPA Scan succeeds, then the settings in the Session Profile are applied to the session.
    • If the EPA Scan fails, then the Session Profile is ignored. Other Session Policies expressions are still evaluated. Remember, Session Policy/Profiles merge, so all applicable Session Policies must be considered.
    • A limitation of this EPA method is that nothing negative happens. Instead, you typically design higher priority number (lower priority) Session Policies with restrictive settings so that if the EPA Scans fail, then users still get something. For example, you can configure your highest priority number Session Policy/Profile with StoreFront (ICA Proxy) only. In the lower priority number Session Policies/Profiles, VPN might be enabled, but only if the EPA scan succeeds. More restrictive Session Profiles usually uncheck Client Choices, and enable Clientless Access or ICA Proxy.
    • This method of EPA Scans is used in SmartAccess and SmartControl configurations.
    • EPA expressions are not supported in Default Syntax, so you’ll need to use Classic Syntax instead.
  • Session Profile > Security tab > Advanced Settings > Client Security Check String
    • If the EPA Scan succeeds, add the user to the listed Authorization AAA Groups.
    • If the EPA Scan fails, add the user to the selected Quarantine Group, and remove the user from all other AAA Groups.
    • If Quarantine Group is not defined, then prevent SSL VPN. Other methods of connecting (Clientless, StoreFront), still work.
  • Assigning EPA scans to Session Policies and Session Profiles is also known as Post-Authentication EPA Scans.
  • If Endpoint Analysis is configured anywhere, then an Endpoint Analysis plug-in is downloaded to the Windows or Mac client.

Prerequisites

Gateway Universal Licenses

Except for ICA Proxy, all NetScaler Gateway connection methods require a NetScaler Gateway Universal License for each concurrent session. Go to System > Licenses and make sure NetScaler Gateway User licenses are installed. Most NetScaler Editions come with built-in licenses.

DNS Name Servers

DNS usually needs to function across the VPN tunnel. Go to Traffic Management > DNS > Name Servers to add DNS servers.

AAA Groups

  1. Edit your LDAP Policy/Server, and make sure Group Extraction is configured. Configure the Group Attribute and the Sub Attribute Name. This causes NetScaler to extract the user’s AD groups when the user logs in using LDAP.
  2. Go to NetScaler Gateway > User Administration > AAA Groups.
  3. On the right, click Add.
  4. Enter a case sensitive group name that matches the group name in Active Directory. Click OK.
  5. On the right, in the Advanced Settings column, you can see the types of objects that can be bound to AAA Groups. These objects are detailed later in this post.

Create Session Profile

To enable SSL VPN: first create the Session Profile. Then create a Session Policy.

You can create multiple Session Policies/Profiles with different settings. Then you can bind these Session Policies to AAA groups and/or NetScaler Gateway Virtual Servers. The Session Profiles are merged, and if conflicts, lower priority bind points win.

To enable SSL VPN in a Session Profile:

  1. On the left, expand NetScaler Gateway, expand Policies, and click Session.
  2. On the right, switch to the Session Profiles tab, and click Add.
  3. Name the profile VPN or similar.
  4. In Session Profiles, every field has an Override Global checkbox to the right of it. If you check this box next to a particular field, then you can configure that field, and the field in this session profile will override settings configured globally (NetScaler Gateway > Global Settings > Change Global Settings), or in a lower priority (higher priority number) session policy.

Network Configuration tab

  1. In the Session Profile, switch to the Network Configuration tab.
  2. You will find a setting that lets you select a DNS Virtual Server. Or if you don’t select anything, then the tunnel will use the DNS servers configured under Traffic Management > DNS > Name Servers.

Client Experience Tab

  1. In the Session Profile, switch to the Client Experience tab. This tab contains most of the NetScaler Gateway VPN settings.
  2. Override Plug-in Type, and set it to Windows/Mac OS X.
  3. On the Client Experience tab, override Split Tunnel and make your choice. Setting it to OFF will force all traffic to use the tunnel. Setting it to ON will require you to create Intranet Applications so the NetScaler Gateway Plug-in will know which traffic goes through the tunnel, and which traffic goes directly out the client NIC (e.g. to the Internet). REVERSE means all traffic goes through the tunnel except for the addresses defined in Intranet Applications.
  4. On the Client Experience tab, there are timers that can be configured. Global Settings contains default timers, so you might want to configure this Session Profile to override the defaults and increase the timeouts. See Configuring Time-Out Settings at Citrix Docs for details.
    1. Client Idle Time-out is a NetScaler Gateway Plug-in timer that disconnects the session if there is no user activity (mouse, keyboard) on the client machine.
    2. Session Time-out is a NetScaler timer that disconnects the session if there is no network activity for this duration.
    3. In addition to these two timers, on the Network Configuration tab, under Advanced Settings
    4. There’s a Forced Timeout setting.

  5. By default, once the VPN tunnel is established, a portal page appears containing Gateway Bookmarks, and StoreFront published icons. An example of the portal page in the RfWebUI theme is shown below:

    1. The X1 theme is shown below:
  6. On the Client Experience tab, the Home Page field lets you override the the default portal page, and instead display a different webpage (e.g. Intranet). This homepage is displayed after the VPN tunnel is established (or immediately if connecting using Clientless Access).
  7. NetScaler Gateway can automatically start the VPN tunnel whenever the user is remote. On the Client Experience tab, click the plus icon next to AlwaysON Profile Name.

    1. Give the profile name. Hover over the question marks to see what each of them does.
    2. Then click Create.
    3. More info at AlwaysON at Citrix Docs.
  8. Additional VPN settings can be found by clicking Advanced Settings near the bottom of the Client Experience tab.
  9. Under Client Experience > Advanced Settings, on the General tab, there are settings to run a login script at login, enable/disable Split DNS, and enable Local LAN Access. Use the question marks to see what they do.
  10. Note: if Split Tunnel is OFF, and if Split DNS is set to REMOTE, NetScaler only returns one IP address to DNS queries. This behavior can be changed by following Citrix CTX200243 DNS Query Responds with Only One IP to Client PC When Connected Through NetScaler Gateway Full VPN.
  11. Under Client Experience > Advanced Settings, on the General tab, is a checkbox for Client Choices. This lets the user decide if they want VPN, Clientless, or ICA Proxy (StoreFront). Without Client Choices, one of the connection methods will occur automatically, depending on what’s enabled.
  12. An example of Client Choices is shown below:

    1. On the main Client Experience tab, if you enabled Client Choices, you can set Clientless Access to Off to add Clientless to the list of available connection methods in the Client Choices screen. Note: this used to be Allow in NetScaler 11.1 and older.
  13. The Client Experience > Advanced Settings section has additional tabs. A commonly configured tab is Proxy, which allows you to enable a proxy server for VPN users.

Security Tab

  1. Back in the main Session Profile, switch to the Security tab.
  2. Set the default authorization to Allow or Deny. If Deny (recommended), you will need to create authorization policies to allow traffic across the tunnel. You can later create different authorization policies for different groups of users.

Published Applications Tab

  1. On the Published Applications tab, set ICA Proxy to Off. This ensures VPN is used instead of ICA Proxy.
  2. Configure the Web Interface Address to embed StoreFront into the default Clientless Access portal page.
    • Note: for X1 theme, additional iFrame configuration is required on the StoreFront side as detailed below. RfWebUI theme does not need any StoreFront changes.
    • From Michael Krasnove: if you configured the Session Policy to direct users to StoreFront, but aren’t using RfWebUI, then placing the following code in c:\inetpub\wwwroot\Citrix\StoreWeb\custom\script.js will cause StoreFront to end the VPN tunnel when the user logs off of StoreFront.
      var LOGOFF_REDIRECT_URL = 'https://YourGatewayFQDN.com/cgi/logout';
       
      // Prevent the default "logoff" screen from being displayed
      CTXS.Controllers.LogoffController.prototype._handleLogoffResult = $.noop;
       
      CTXS.Extensions.afterWebLogoffComplete = function () {
       window.location.href = LOGOFF_REDIRECT_URL;
      };
  3. See the ICA Proxy post for more information on integrating StoreFront with NetScaler Gateway.

Other Tabs

  1. The Remote Desktop tab is detailed in the RDP Proxy post.
  2. The PCoIP tab is detailed in the PCoIP Proxy post.
  3. Click Create when you’re done creating the Session Profile.

Create Session Policy

Once the Session Profile is created, you need a Session Policy linked to it. The Session Policy contains an expression, where if true, then the Session Profile is applied.

If multiple Session Policies apply to a particular connection, then the settings in the policies are merged. For conflicting settings, the Session Policy with the highest priority (lowest priority number) wins. Session Policies bound to AAA groups only override Session Policies bound to NetScaler Gateway Virtual Servers if the AAA group bind point has a lower priority number. In other words, priority numbers are evaluated globally no matter where the Session Policy is bound. You can run the command nsconmsg –d current –g pol_hits to see which Session Policies are applying to a particular connection. See CTX214588 Understanding Session Policy Priority on Different Bind Points.

You can also include Endpoint Analysis expressions in a Session Policy, so that the Session Policy only applies to machines that pass the Endpoint Analysis scan. However, EPA Scans are only supported with Classic Syntax policy expressions, and not with Default Syntax.

To create a Session Policy that is linked to a Session Profile:

  1. On the left, go to NetScaler Gateway > Policies > Session.
  2. In the right pane, switch to the Session Policies tab, and click Add.
  3. Give the policy a descriptive name.
  4. Change the Profile drop-down to the VPN Profile you just created.
  5. The Expression box has an option for switching to Default Syntax.

    1. If Default Syntax, enter true in the Expression box so it always evaluates to true. If Classic Syntax, it would be ns_true instead of true.
    2. If Default Syntax, you can enter HTTP.REQ.USER.IS_MEMBER_OF("MyADGroup") to restrict the Session Profile to members of a specific AD group. In Classic Syntax, this isn’t possible in an expression, and instead you must assign the Session Policy to a AAA Group.
  6. If Classic Syntax, you can add Endpoint Analysis scans to the Expression box. If the Endpoint Analysis scan succeeds, then the session policy is applied. If the Endpoint Analysis scan fails, then this session policy is skipped, and the next one is evaluated. This is how you can allow VPN if EPA scan succeeds, but all failed EPA scans will get a different session policy that only has ICA Proxy enabled.
    1. To add an Endpoint Analysis scan, use one of the Editor links on the right.
    2. Configure OPSWAT scans in the OPSWAT EPA Editor.
    3. Configure Client Security Expressions in the Expression Editor.
    4. You can combine multiple Endpoint Analysis scan expressions using Booleans (&&, ||, !).
  7. Click Create when done.

Bind Session Policy

Most of the NetScaler Gateway configuration objects can be bound to a NetScaler Gateway Virtual Server, AAA Groups, or both. This section details binding of Session Policies, but the other NetScaler Gateway objects (e.g. Authorization Policies) can be bound using similar instructions.

  • Objects bound directly to the NetScaler Gateway Virtual Server are evaluated for every user of that Gateway Virtual Server.
  • Objects bound to a AAA Group are only evaluated for members of that AAA Group.
    • Polices bound to AAA Groups usually have lower priority numbers than policies bound to Gateway Virtual Servers, so the AAA binding can override the Gateway binding.
    • However, objects/policies bound to a AAA Group are applied to every Gateway Virtual Server on the same appliance. To override AAA bindings at a specific Gateway, you can bind lower priority number policies to the Gateway Virtual Server.

Bind the new Session Policy to a NetScaler Gateway Virtual Server, or a AAA group.

To bind to a NetScaler Gateway Virtual Server

  1. Edit a NetScaler Gateway Virtual Server (or create a new one).
  2. To make sure ICA Only is unchecked:
    1. Click the pencil icon for the Basic Settings section.
    2. Click More.
    3. Make sure ICA Only is unchecked, and click OK to close the Basic Settings section.
    4. Note: with this box unchecked, Gateway Universal licenses are now required for all users connecting through this Gateway Virtual Server.
  3. While editing the Gateway Virtual Server, consider changing the Portal Theme to RfWebUI. This changes the default portal page to look identical to StoreFront.
  4. Scroll down to the Policies section, and click the Plus icon.
  5. In the Choose Type page, ensure the Choose Policy drop-down is set to Session.
  6. Ensure the Choose Type drop-down is set to Request, and click Continue.
  7. Click where it says Click to select.

    1. If you already have Session Policies bound to this Gateway Virtual Server, then you might have to click Add Binding first.
  8. Click the radio button next to the previously created Session Policy, and click Select.
  9. Note: you cannot mix Classic Syntax Policies and Default Syntax Policies.
  10. In the Priority field, adjust the priority number. If you want this Session Policy to override other Session Policies, then set the priority number to a low value. See CTX214588 Understanding Session Policy Priority on Different Bind Points.
  11. Click Bind.
  12. If you already have Session Policies bound to the Gateway Virtual Server, then the list of Policies is displayed. If you don’t see this list, on the left, in the Policies section, click the line that says Session Policies.
  13. From this list, you can right-click the policies to Edit Binding (priority number), or Edit Profile.

Bind to AAA Group

  1. To bind to a AAA Group, go to NetScaler Gateway > User Administration > AAA Groups.
  2. On the right, add a AAA group with the same name (case sensitive) as the Active Directory group name. This assumes your LDAP policies/server are configured for group extraction (Group Attribute, and Sub Attribute).
  3. Edit the AAA Group.
  4. On the right, in the Advanced Settings column, add the Policies section.
  5. Click the plus icon to bind one or more Session Policies.
  6. If you want these Session Policies to override the Session Policies bound to the NetScaler Gateway Virtual Server, then make sure the Session Policies bound to the AAA Group have lower priority numbers. See CTX214588 Understanding Session Policy Priority on Different Bind Points.


NetScaler Gateway Plug-in Installation

Here is what the user sees when launching the VPN session for the first time. This assumes the user is an administrator of the local machine.



And then the default portal page is displayed. If using the RfWebUI theme, it might prompt you to install Receiver.

Only administrators can install the NetScaler Gateway Plug-in. You can download the Gateway plug-in from the NetScaler appliance at /var/netscaler/gui/vpns/scripts/vista and push it to corporate-managed machines. Or you can download VPN clients from Citrix.com. The VPN client version must match the NetScaler firmware version.

While a VPN tunnel is established, you can open the Gateway Plug-in to see status. If the Gateway Plug-in is merged with Receiver, right-click Receiver, click Advanced Preferences, click NetScaler Gateway Settings, and click Open.

Or, if the Gateway Plug-in icon is separated from Receiver, then right-click the Gateway Plug-in icon, and click Open.

The hamburger menu on the left lets you see more info about the VPN tunnel.

If the Gateway VPN session isn’t established, you can open the Gateway plug-in, and login. No browser needed.

The Configuration page lets you enable Logging. Then the Logging page lets you collect the logs. See Citrix CTX138155 How to Collect Client VPN Logs for NetScaler Gateway.

VPN Client (NetScaler Gateway Plug-in) Session Profile Settings

Separate Icons for Receiver and Gateway

  1. By default, if Receiver, and NetScaler Gateway Plug-in, are installed on the same machine, then the icons are merged. To see the NetScaler Gateway Plug-in Settings, you right-click Receiver, open Advanced Preferences, and then click NetScaler Gateway Settings. This makes it difficult to log off.

  2. You can configure the Session Profile to prevent the NetScaler Gateway Plug-in from merging with Receiver. Edit your VPN Session Policy/Profile. On the Client Experience tab…
  3. Scroll down, and check the box next to Advanced Settings.
  4. At the bottom of the General tab, check the box next to Show VPN Plugin-in icon with Receiver.
  5. This setting causes the two icons to be displayed separately thus making it easier to access the NetScaler Gateway Plug-in settings, including Logoff.

Cleanup

  1. When the user logs off of VPN, a Cleanup page is displayed. This can be enabled or disabled in a Session Profile on the Client Experience tab.

  2. The cleanup options can be forced in a Session Profile on the Client Experience tab…
  3. Under Advanced Settings > Client Cleanup.

VPN Client Upgrades

  1. Whenever NetScaler firmware is upgraded, all users will be prompted to upgrade their VPN clients. You can edit a Session Policy/Profile, and on the Client Experience tab…
  2. Use the Upgrade drop-downs to disable the automatic upgrade.
  3. The Plugin Upgrade settings are also configurable in the Gateway Virtual Server…
  4. In the Basic Settings > More section.


Authorization Policies

If your Session Profile has Security tab > Default Authorization Action set to Deny (recommended), then create Authorization Policies to allow access across the tunnel.

  1. On the left, under NetScaler Gateway, expand Policies, and click Authorization.
  2. On the right, click Add.
  3. Name the Authorization Policy.
  4. Select Allow or Deny.
  5. For the Expression, NetScaler Gateway 12 supports both Classic Syntax and Default Syntax.
    • Default Syntax gives you much greater flexibility in matching the traffic that should be allowed or denied. Hit Control+Space on your keyboard to begin building a Default Syntax expression. You typically want to identify traffic based on Destination IP Address, Destination Port Number, HTTP Request URL, HTTP Host Header, etc. Common expressions include:
      • CLIENT.IP.DST.IN_SUBNET()
      • CLIENT.TCP.DSTPORT.EQ()
      • You can also use HTTP.REQ.USER.IS_MEMBER_OF("MyADGroup") in your expressions.
    • Note: you cannot mix both Classic Syntax and Default Syntax. You must unbind every Classic Syntax Authorization Policy before you can bind Default Syntax Authorization Policies.
  6. Click Create when done.
  7. Authorization Policies are usually bound to AAA groups. This allows different groups to have different access across the tunnel.
    1. Or, you can use HTTP.REQ.USER.IS_MEMBER_OF("MyADGroup") in your Default Syntax expressions.
  8. Edit a AAA Group at NetScaler Gateway > User Administration > AAA Groups.
  9. On the right, in the Advanced Settings column, add the Authorization Policies section.
  10. Then click where it says No Authorization Policy to bind policies.

Intranet Applications

If you enabled Split Tunnel, then you’ll need to create Intranet Applications to specify which traffic goes through the tunnel.

  1. On the left, under NetScaler Gateway, expand Resources, and click Intranet Applications.
  2. On the right, click Add.

    1. Enter a name for the Internal subnet.
    2. Change the Interception Mode to TRANSPARENT.
    3. Enter an IP subnet. Only packets destined for this network go across the tunnel.
      1. You typically specify a summary address for all internal subnets (e.g. 10.0.0.0/8).
      2. Alternatively, you can define minimal Intranet Application destinations as a security mechanism (assuming Split Tunnel is enabled), but Authorization Policies are more appropriate for that task.
  3. Click Create.
  4. Create additional Intranet applications for each internal subnet.
  5. Intranet Applications are usually bound to the Gateway Virtual Server, but you can also bind them to AAA Groups.
  6. On the right, in the Advanced Settings column, add the Intranet Applications section.
  7. On the left, click No Intranet Application to bind Intranet Applications.

DNS Suffix

Specify a DNS Suffix for Split DNS to function with single label DNS names. NetScaler Gateway adds these DNS suffixes to DNS queries across the VPN tunnel.

  1. On the left, under NetScaler Gateway, expand Resources, and click DNS Suffix.
  2. On the right, click Add.
  3. Enter the DNS Suffix, and click Create. You can add multiple suffixes.

Bookmarks

Bookmarks are the links that are displayed in the default portal interface. They can point to websites, or RDP addresses. PCoIP bookmarks come from VMware Horizon Connection Server. ICA bookmarks come from Citrix StoreFront.

  1. Under NetScaler Gateway, expand Resources, and click Bookmarks.
  2. On the right, click Add.

    1. Give the bookmark a name, and display text.
    2. Enter a website or RDP address.
    3. Optionally browse to an Icon file.
    4. You typically need to check Use NetScaler Gateway As a Reverse Proxy, especially for Clientless Access (rewrite without VPN) to an internal website.
    5. The other fields are for Single Sign-on through Unified Gateway.
  3. Click Create.
  4. Bookmarks (aka Published Applications > Url) are usually bound to AAA groups so different groups can have different bookmarks. But it’s also possible to bind Bookmarks to NetScaler Gateway Virtual Servers.
  5. If NetScaler Gateway Virtual Server, add the Published Applications section to bind Bookmarks (Url).
  6. For AAA Group, it’s the Bookmarks section.
  7. On the left, find the Published Applications section, and click No Url to bind Bookmarks.

VPN Client IP Pools (Intranet IPs)

By default, NetScaler Gateway VPN clients use NetScaler SNIP as their source IP when communicating with internal resources. To support IP Phones or endpoint management, you must instead assign IP addresses to VPN clients.

Any IP pool you add to NetScaler must be reachable from the internal network. Configure a static route on the upstream router. The reply traffic to VPN Client IPs should be routed through a NetScaler SNIP. Or the NetScaler can participate in OSPF.

When a client is assigned a client IP, this IP address persists across multiple sessions until the appliance reboots, or until the appliance runs out of IPs in the pool.

  1. Edit a NetScaler Gateway Virtual Server, or a AAA group.
  2. On the right, in the Advanced Settings section, click the plus icon next to Intranet IP Addresses.
  3. On the left, click where it says No Intranet IP.
  4. Enter a subnet and netmask. Click Bind.
  5. In a Session Profile, on the Network Configuration tab, check the box next to Advanced Settings.
  6. Use the Intranet IP drop-down to configure the behavior when there are more VPN clients than available IPs in the address pool.

    1. If you set it to NOSPILLOVER, then users can only have one VPN session, as described in CTX218066 How to Limit One Session Per User on NetScaler Gateway?.


  7. To see the Client IP address, on the client side, after the tunnel is established, right-click the NetScaler Gateway Plug-in, and click Open.
  8. See the Internal network address.
  9. To see the client IP on the NetScaler, go to NetScaler Gateway, and on the right is Active user sessions.
  10. Select one of the views, and click Continue.
  11. The right column contains the Intranet IP.

StoreFront in Gateway X1 Portal

If you enabled the RfWebUI theme, then no StoreFront configuration is necessary.

But if you want to embed StoreFront in the other Gateway themes (X1, Default, Green Bubble), then follow these instructions.

  1. On StoreFront, edit the file C:\Inetpub\wwwroot\Citrix\StoreWeb\web.config.
    1. On the bottom, there are three sections containing X-Frame-Options. Change all three of them from deny to allow.
    2. Also change frame-ancestors from none to self.
  2. In NetScaler, go to NetScaler Gateway > Global Settings, and click Configure Domains for Clientless Access.
  3. Change the selection to Allow Domains, enter your StoreFront FQDN, and click the plus icon.
  4. Click OK.
  5. In a Session Policy/Profile:
    1. On the Client Experience tab, make sure Single Sign-on to Web Applications is enabled.
    2. On the Published Applications tab, configure the Web Interface Address to point to the StoreFront Receiver for Web page.
    3. Configure the Single Sign-on domain to match what’s configured in StoreFront.
  6. The Applications page of the 3-page portal (e.g. X1 theme) should automatically show the StoreFront published icons.

Quarantine Group

NetScaler Gateway can be configured so that if Endpoint Analysis scans fail, then the user is placed into a Quarantine Group. You can bind session policies, authorization policies, etc. to this quarantine group. Policies bound to other AAA groups are ignored.

  1. Go to NetScaler Gateway > User Administration > AAA Groups.
    1. Add a new local group for your Quarantined Users. This group is local, and does not need to exist in Active Directory.
    2. Bind session policies, authorization policies, etc. to your quarantine AAA group. These policies typically allow limited access to the internal network so users can remediate. Or, it might simply display a webpage telling users how to become compliant.
    3. The Session Policy bound to the Quarantine Group is usually different than the Session Policies bound to other AAA groups. You can use the variation in Session Policy names for SmartAccess.
      1. One option is to configure the Delivery Groups > Access Policy so that icons are shown for Session Policies bound to non-quarantine AAA Groups, but not for the Session Policy that is bound to the Quarantine Group.
      2. Another option is to configure Citrix Policies > Access Control to disable functionality for the Quarantine Group Session Policy, but not for other AAA Group Session Policies.
  2. Create or edit a Session Profile to include a Client Security Expression that checks for compliance.
    1. In the Session Profile, on the Security tab, check the box next to Advanced Settings.
    2. Scroll down, and check the box to the right of Client Security Check String.
    3. Use the Editor links to add an Endpoint Analysis expression.
    4. Just below the Client Security Check String, select the previously created Quarantine Group. If the Client Security Check String EPA Scan fails, then the failed users are added to the Quarantine Group and removed from all other AAA Groups.
  3. Click Create when done creating or editing the Session Profile.
  4. Create a Session Policy for the Session Profile that contains the Client Security Check String.
    1. Enter ns_true as the expression.
    2. Then click Create.
  5. Edit your Gateway Virtual Server, and bind the Session Policy/Profile that has the Client Security Check String configured.


  6. To troubleshoot Quarantine policies, use the command nsconmsg –d current –g pol_hits.
  7. NetScaler MAS Gateway Insight shows users that failed EPA scans, and their quarantine status.

Related Pages

NetScaler Gateway 12 – RDP Proxy

Last Modified: Aug 28, 2017 @ 6:50 pm

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RDP Proxy Overview

NetScaler supports RDP Proxy through NetScaler Gateway. No VPN required. RDP can connect through NetScaler Gateway on port 443.

There are several ways of launching RDP sessions through NetScaler Gateway RDP Proxy:

  • Bookmarks on the Clientless Access portal page.
    • Bookmarks can be defined by the administrator.
    • Or users can add their own RDP bookmarks.
  • After logging in, change the URL in the browser to /rdpproxy/MyRDPServer. MyRDPServer can be IP or DNS.
  • In the RfWebUI Portal Theme, the Bookmark link lets users enter an RDP address, and click Go.

Links:

Requirements

Here are some requirements for RDP Proxy:

  • NetScaler Enterprise Edition or Platinum Edition.
  • NetScaler Gateway Universal Licenses for each user.
    • Most NetScaler Editions come with built-in Gateway Universal licenses: NetScaler Standard Edition = 500 licenses, NetScaler Enterprise Edition = 1000 licenses, and NetScaler Platinum Edition = unlimited licenses. See Feature Licensing in the Gateway Tweaks post.
  • TCP 443 opened to the NetScaler Gateway Virtual Server.
  • TCP 3389 opened from the NetScaler SNIP to the RDP Servers.

Configuration

Enable RDP Proxy Feature

  1. Go to System > Settings, and click Configure Advanced Features.
  2. In the left column, near the bottom, check the box for RDP Proxy, and click OK.

Create RDP Proxy Profile

  1. Expand NetScaler Gateway, expand Policies, and click RDP.
  2. On the right, switch to the Client Profiles tab, and click Add.

    1. Give the RDP Client Profile a name, and configure it as desired. Scroll down.
    2. It is no longer necessary to configure a Pre shared key or RDP Host. Just click Create.
  3. It is no longer necessary to create a RDP Server Profile.

Create RDP Bookmarks

  1. If you want to put RDP bookmarks on the Clientless Access portal page, on the left, expand NetScaler Gateway, expand Resources, and click Bookmarks.
  2. Alternatively, Simon Gottschlag Publish RDP Proxy Link via StoreFront shows how NetScaler Rewrite can insert an RDP Proxy link into a StoreFront web page.
  3. On the right, click Add.

    1. Give the Bookmark a name.
    2. For the URL, enter rdp://MyRDPServer using IP or DNS (FQDN).
    3. Check the box next to Use NetScaler Gateway As a Reverse Proxy,
  4. Click Create.
  5. Create more bookmarks as desired.

Edit a Session Profile

  1. Create or edit a Session Profile.
  2. On the Security tab, set Default Authorization Action to ALLOW. Or you can use Authorization policies to control access.
  3. On the Remote Desktop tab, check Override Global, and select the RDP Client Profile you created earlier.
  4. If you want to use Bookmarks, on the Client Experience tab, set Clientless Access to On.
  5. On the Published Applications tab, make sure ICA Proxy is OFF.
  6. Click OK when done.

Edit NetScaler Gateway Virtual Server

  1. Edit or Create your Gateway Virtual Server.
  2. In the Basic Settings section, click the pencil icon to edit it, and click More to show more settings.

    1. It is no longer necessary to bind a RDP Server Profile. Instead, RDP is proxied through 443 on the Gateway.
    2. Scroll down. Make sure ICA Only is not checked. This means you’ll need NetScaler Gateway Universal licenses for each user that connects through this Gateway.
    3. Click OK to close the Basic Settings section.
  3. Bind a certificate.
  4. Bind authentication policies.
  5. In the Policies section, bind the Session Policy that has the RDP Client Profile configured.


  6. You can bind RDP Bookmarks to either the NetScaler Gateway Virtual Server, or to a AAA group. To bind to the NetScaler Gateway Virtual Server, on the right, in the Advanced Settings section, click Published Applications.
  7. On the left, in the Published Applications section, click where it says No Url.
  8. Bind your Bookmarks.

  9. While editing your Gateway vServer, you can also enable the RfWebUI Portal Theme.

Configure DNS

  1. If you want to connect to RDP servers using DNS, make sure DNS servers are configured on the appliance (Traffic Management > DNS > Name Servers).
  2. If you want to use the short names instead of FQDNs, add a DNS Suffix (Traffic Management > DNS > DNS Suffix).

Use RDP Proxy

  1. Connect to your Gateway and login.
  2. If you configured Bookmarks, if RfWebUI theme, on the Apps tab, click Web and SaaS Apps.

    1. If X1 theme, the bookmarks are on the Web Apps page.
  3. If RfWebUI theme, you can click Details to mark the Bookmark as a Favorite.

  4. Or you can change the address bar to /rdpproxy/MyRDPServer. You can enter an IP address (e.g. rdpproxy/192.168.1.50) or a DNS name (/rdpproxy/myserver).
  5. If you edit the downloaded .rdp file, notice that it’s connecting on port 443.
  6. Then open the downloaded .rdp file.
  7. You can view the currently connected RDP users by going to NetScaler Gateway > Policies > RDP, and on the right, is the Connections tab.

Personal Bookmarks

  1. If using the RfWebUI theme, another way to launch RDP sessions is to click the Bookmark link, enter a destination DNS/IP, check the box next to RDP Link, and click Go.
  2. You can also give the Bookmark a name and Save it.
  3. Then access the saved bookmark from Apps > Personal Bookmarks.

  4. Personal bookmarks are stored in /var/vpn/bookmark on the appliance. You might want to back these up and replicate them to other Gateway appliances participating in GSLB. See NetScaler 11.1 Personal Bookmarks at Citrix Discussions.
  5. The X1 theme has an Add button on the Web Apps page.
  6. But there is no Go button. Instead, you save the Bookmark and launch it from the list.

SmartAccess / SmartControl – NetScaler Gateway 12

Last Modified: Sep 16, 2017 @ 1:59 pm

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SmartAccess / SmartControl

SmartAccess and SmartControl let you change ICA connection behavior (e.g. disable client device mappings, hide icons) based on how users connect to NetScaler Gateway. Decisions are based on NetScaler Gateway Virtual Server name, Session Policy name, and Endpoint Analysis scan success or failure.

SmartAccess vs SmartControl:

  • SmartAccess lets you control visibility of published icons, while SmartControl does not.
  • SmartControl is configured exclusively on NetScaler, while SmartAccess requires configuration on both NetScaler, and inside Citrix Studio.
  • SmartControl requires NetScaler Platinum Edition licensing, while SmartAccess is available in all NetScaler Editions.
    • Both features require NetScaler Gateway Universal licenses for every concurrent connection.

Prerequisites

Both SmartAccess and SmartControl have the same prerequisites. You can configure SmartAccess in XenApp/XenDesktop at any time, but it won’t work, until you do the following:

  1. NetScaler appliance license: See Feature Licensing in the Gateway Tweaks post. In summary:
    • SmartAccess is available in all editions of NetScaler appliances.
    • SmartControl is available only in NetScaler Platinum Edition.
  2. NetScaler Gateway Universal Licenses – On the NetScaler, go to System > Licenses, and make sure you have NetScaler Gateway Universal Licenses allocated to the appliance.
    1. Most NetScaler Editions (except NetScaler Gateway Enterprise VPX) come with built-in Gateway Universal licenses: NetScaler Standard Edition = 500 licenses, NetScaler Enterprise Edition = 1,000 licenses, and NetScaler Platinum Edition = unlimited licenses.
    2. Additional NetScaler Gateway Universal licenses can be acquired through other means. See Feature Licensing in the Gateway Tweaks post for details.
    3. The Universal licenses are allocated to the hostname of the appliance (click the gear icon to change it), not the MAC address. In a High Availability pair, if each node has a different hostname, then you can allocate the licenses to one hostname, then reallocate to the other hostname. See Feature Licensing in the Gateway Tweaks post for details.

  3. NetScaler Gateway must have ICA Only unchecked.
    1. On the NetScaler, go to NetScaler Gateway > Virtual Servers, and edit your Gateway Virtual Server.
    2. In the Basic Settings section, click the pencil icon.
    3. Click More.
    4. Uncheck the box next to ICA Only, and click OK. This tells NetScaler Gateway to start using Universal licenses, and enables the SmartAccess and SmartControl features.
  4. Enable Trust XML on the XenDesktop Site/Farm:
    1. On a XenApp/XenDesktop Controller, run PowerShell as Administrator.
    2. Run asnp citrix.* to load the snapins.
    3. Run Set-BrokerSite -TrustRequestsSentToTheXmlServicePort $true to enable Trust XML.
  5. Configure Callback URL in StoreFront:
    1. In StoreFront Console, right-click the Stores node, and click Manage NetScaler Gateways.
    2. Edit a Gateway.
    3. On the Authentication Settings page, make sure a Callback URL is configured. The Callback URL must resolve to a NetScaler Gateway VIP on the same appliance that authenticated the user. The Callback Gateway’s certificate must match the FQDN entered here. If you are configuring Single FQDN for internal and external, then the Callback FQDN must be different than the Single FQDN.

Once the prerequisites are in place, do the following as detailed below:

Endpoint Analysis

Endpoint Analysis (EPA) scans are completely optional. You can configure SmartControl and SmartAccess without implementing any Endpoint Analysis.

Endpoint Analysis is supported on Windows and Mac devices, and only from a web browser (not from native Receiver). Other devices, like iOS and Android, do not support Endpoint Analysis. If you want to allow mobile device connectivity, then make sure you have an access mechanism (e.g. ICA Proxy) that works if the Endpoint Analysis scan fails.

EPA Policies

There are two methods of Endpoint Analysis: pre-authentication and post-authentication. For pre-authentication, configure an Endpoint Analysis expression in a Preauthentication Policy. For post-authentication, configure the Endpoint Analysis expression on one or more Session Policies.

  • With a Preauthentication Policy, if the Endpoint Analysis scan fails, then users can’t login.
  • With a Postauthentication Policy, Endpoint Analysis doesn’t run until after the user logs in. Typically, you create multiple Session Policies. One or more Session Policies have Endpoint Analysis expressions. Leave one policy without an Endpoint Analysis expression so there’s a fallback in case the client device doesn’t support Endpoint Analysis (e.g. mobile devices). The name of the Session Policy is then used later in Citrix Policies and Citrix Delivery Groups.
    • Inside the Session Profile is a field for Client Security expression, which supports an EPA expression. This field is for VPN only, and does not affect SmartAccess.

Preauthentication Policies and Profiles are configured at NetScaler Gateway > Policies > Preauthentication.

  1. On the right, switch to the Preauthentication Profiles tab, and create a Preauthentication Profile to allow access.

  2. Switch to the Preauthentication Policies tab, and create a Preauthentication Policy with an EPA expression. Select the Request Action that allows access.

  3. The right side of the Expression box has links to create EPA expressions, as detailed below.

Post-authentication Policies and Profiles are configured at NetScaler Gateway > Policies > Session.

  1. When creating a Session Policy, the right side of the Expression box has links to create EPA expressions, as detailed below. Note: In NetScaler 12 build 51, the OPSWAT EPA Editor link does not work correctly. But you can use the OPSWAT EPA Editor on a Preauthentication Policy, and then copy the expression to a Session Policy.
  2. Classic Syntax vs Default Syntax – EPA expressions can only be added to Classic Syntax Policies. If you click Switch to Default Syntax, then the OPSWAT EPA Editor disappears.
  3. If you edit a Session Profile, on the Security tab…
  4. Under Advanced Settings, you will see a Client Security Check String box that lets you enter an EPA Expression. This field applies to VPN only, and does not affect SmartAccess.

EPA Expressions

NetScaler has two Endpoint Analysis engines: the original Client Security engine, and the newer OPSWAT EPA engine.

  • Both EPA expression types require the Session Policy to be Classic Syntax. If you see any messages about Classic Syntax being deprecated, ignore those messages.

OPSWAT EPA Expressions

To configure OPSWAT EPA expressions:

  1. When creating a Preauthentication Policy or Session Policy, click the OPSWAT EPA Editor link.
  2. Use the drop-down menus to select the scan criteria.
  3. You will see some fields with a plus icon that lets you configure more details for the scan.

    • Note: the text in these policy expressions is case sensitive.
  4. Then click Done.

Additional OPSWAT EPA Info

See the following links for more Advanced EPA information:

Original Client Security Expressions

To configure the original Client Security expressions:

  1. When creating a Preauthentication Policy or Session Policy, click the Expression Editor link.
  2. Change the Expression Type to Client Security.
  3. Use the Component drop-down to select a component.
    1. A common configuration is to check for domain membership as detailed at Citrix CTX128040 How to Configure a Registry-Based Scan Expression to Look for Domain Membership.
    2. Citrix CTX128039 How to Configure a Registry-Based EPA Scan Expression on NetScaler to Look for the Active Device or Computer Name of an Explicit Workstation  💡

Once the Preauthentication and/or Session Policies are created, bind them to your NetScaler Gateway Virtual Server:

  1. Edit a NetScaler Gateway Virtual Server.
  2. Scroll down to the Policies section, and click the plus icon.
  3. Select either Preauthentication or Session, and select the policy you already created. Then click Bind.
  4. Session Policies with EPA Expressions are typically higher in the list (lower priority number) than non-EPA Session Policies.

EPA and Portal Themes

The webpages displayed to the user when downloading the EPA plug-in and running the EPA plug-in can be customized by editing a Portal Theme.

Look in the Advanced Settings column on the right for the three EPA pages. Citrix CTX222812 How to Customize Custom Error Messages for NetScaler Gateway EPA Scans.  💡

EPA Troubleshooting

From Citrix CTX209148 Understanding/Configuring EPA Verbose Logging Feature:

  1. Go to NetScaler Gateway > Global Settings.
  2. On the right, click Change Global Settings.
  3. On the Security tab, click Advanced Settings.
  4. Scroll down, check the box next to Enable Client Security Logging, and click OK.
  5. When the scan fails, the user is presented with a Case ID.
  6. You can then grep /var/log/ns.log for the Case ID. Or search your syslog.

For client-side logging, on the client machine, go to HKEY_LOCAL_MACHINE\SOFTWARE\Citrix\Secure Access Client.

  • Make a DWORD value named “EnableEPALogging“, and set the value to 1.
  • After attempting the scan again, you’ll find the file %localappdata%\Citrix\AGEE\epaHelper_epa_plugin.txt with details for each scan expression.

NetscalerAssasin EPA OPSWAT Packet flow and Troubleshooting shows a Wireshark trace of an EPA scan.

SmartAccess

Links:

Make sure the prerequisites are completed. This includes:

  • ICA Only unchecked on NetScaler Gateway Virtual Server
  • Gateway Universal licenses installed
  • Callback URL configured at StoreFront
  • Trust XML enabled on Delivery Controllers

SmartAccess is configured in two places:

  • Delivery Group > Access Policy page
  • Citrix Policy (user half only) > filters > Access control

In both cases, you enter the name of a matching Gateway Virtual Server, and the name of a matching Session Policy (or Preauthentication Policy).

  • Set AG farm name or Site or Farm name to the name of the NetScaler Gateway Virtual Server.
  • Set Access condition or Filter to the name of the NetScaler Gateway Session Policy (or Preauthentication Policy).
  • You can use * as a wildcard in either field.
  • The matching NetScaler Gateway Session Policy typically has an EPA Expression configured in the Policy Rule. That way the Session Policy only applies to connections that match the EPA Expression.

Icon visibility – Access Control at the Delivery Group controls visibility of icons published from that Delivery Group.

  • Access Control on a Delivery Group is Allow only. Icons are hidden from non-matching connections.
  • You can uncheck Connections through NetScaler Gateway to hide the published icons from all NetScaler Gateway connections.
  • It’s not possible to hide individual published applications. You can hide all applications from a single Delivery Group, or none of them. If you need more granularity, then you’ll have to split the applications onto different Delivery Groups.
  • App Groups do not have an Access Control option. It’s Delivery Groups only.

Citrix Policy Settings – Access Control filter on a Citrix Policy determines if the Policy settings apply or not.

  • Access Control filter applies to User Settings only. It’s not configurable for Computer Settings.
  • You typically configure the Unfiltered Citrix Policy to block all client device mappings. Then you configure a higher priority Citrix Policy with Access Control filter to re-enable client device mappings for endpoint machines that match the Session Policy and EPA Expression.

When connected to a session, Director shows SmartAccess Filters on the Session Details page. Notice the Farm Name (Gateway Virtual Server name) and Filter Name (Session Policy name)

SmartControl

The SmartControl feature lets you configure some of the SmartAccess functionality directly on the appliance. See Configuring SmartControl at Citrix Docs for detailed instructions.

  • Note: SmartControl requires NetScaler Platinum Edition. If you don’t have Platinum Edition, you can instead configure SmartAccess.
  • SmartControl cannot hide published icons. If you need that functionality, configure SmartAccess, either as a replacement for SmartControl, or as an addition to SmartControl.

To configure SmartControl:

  1. Make sure the Prerequisites are completed. This includes: ICA Only unchecked, Gateway Universal licenses installed, Callback URL configured at StoreFront, and Trust XML enabled on Delivery Controllers.
  2. If you are using a Preauthentication Policy to run an Endpoint Analysis scan:
    1. Edit the Preauthentication Profile.
    2. Configure the Default EPA Group with a new group name. You’ll use this group name later.
  3. If you are instead using a Session Policy to run the post-authentication Endpoint Analysis scan:
    1. Edit the Session Profile
    2. On the Security tab, use the Smartgroup field to define a new group name for users that pass the scan. You’ll use this group name later.
  4. On the left, expand NetScaler Gateway, expand Policies, and click ICA.
  5. On the right, switch to the Access Profiles tab, and click Add.

    1. Configure the restrictions as desired, and click Create.
  6. Switch to the ICA Action tab, and click Add.

    1. Give the ICA Action a name.
    2. Select the ICA Access Profile.
    3. Click Create.
  7. Switch to the ICA Policies tab, and click Add.
  8. In the Create ICA Policy page, do the following:
    1. Give the ICA Policy a name.
    2. Select the previously created ICA Action.
    3. Enter an expression. You can use HTTP.REQ.USER.IS_MEMBER_OF(“MyGroup”).NOT where MyGroup is the name of the SmartGroup you configured in the session profile or preauth scan.
  9. Click Create when done.
  10. Edit your Gateway Virtual Server.
    1. Scroll down to the Policies section, and click the plus icon.
    2. Change the Choose Type drop-down to ICA, and click Continue.
    3. Select the SmartControl policy you created earlier, and click Bind.

Related Pages

Global Server Load Balancing (GSLB) – NetScaler 12

Last Modified: Aug 25, 2017 @ 11:35 am

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GSLB Planning

GSLB is nothing more than DNS. GSLB is not in the data path. GSLB receives a DNS query, and GSLB sends back an IP address, which is exactly how a DNS server works. The user then connects to the returned IP, which doesn’t even need to be on a NetScaler.

GSLB can do some things that DNS servers can’t do:

  • Don’t give out an IP address unless it is UP (monitoring)
    • If the active IP address is down, then give out the passive IP address (active/passive)
  • Give out the IP address that is closest to the user (proximity load balancing)
  • Give out different IPs for internal users vs external users (DNS View)

GSLB is only useful if you have a single DNS name that could resolve to two or more IP addresses. If there’s only one IP address, then use normal DNS instead.

Citrix Blog Post Global Server Load Balancing: Part 1 explains how DNS queries work and how GSLB fits in.

Citrix has a good DNS and GSLB Primer.

When configuring GSLB, don’t forget to ask “where is the data?”. For XenApp/XenDesktop, DFS multi-master replication of user profiles is not supported, so configure “home” sites for users. More information at Citrix Blog Post XenDesktop, GSLB & DR – Everything you think you know is probably wrong!

GSLB Configuration Overview

GSLB Configuration can be split between one-time steps for GSLB infrastructure, and repeatable steps for each GSLB-enabled DNS name.

One-time GSLB Infrastructure configuration

  1. Create ADNS listener on each NetScaler pair – DNS clients send DNS queries to the ADNS listeners. GSLB resolves a DNS query into an IP address, and returns the IP address in the DNS response.
  2. Create GSLB Sites (aka MEP Listener) – GSLB Sites usually correspond to different datacenters. GSLB Sites are also the IP address endpoints for NetScaler’s proprietary Metric Exchange Protocol (MEP), which is used by GSLB to transmit proximity, persistence, and monitoring information.
  3. Import Static Proximity Database – NetScaler includes a database that can be used to determine the geographical location of an IP address. Or you can subscribe to a geolocation service, and import its database.
  4. Delegate DNS sub-zone to NetScaler ADNS – in the original DNS zone, create a new sub-zone (e.g. gslb.company.com), and delegate the sub-zone to all ADNS listeners.

Repeatable GSLB Configuration for each DNS name:

  1. Create one or more GSLB Services per DNS name, and per IP address response – each GSLB Service corresponds to a single IP address that can be returned in response to a DNS Query.
    • Optionally, bind a Monitor to each GSLB Service. Monitors determine if the GSLB Service is up or not.
  2. Create a GSLB Virtual Server per DNS name
    • Bind a DNS name to the GSLB Virtual Server.
    • For active/active – bind multiple GSLB Services to the GSLB Virtual Server, configure a load balancing method (e.g. proximity), and configure site persistence.
    • For active/passive – bind the active GSLB Service. Create another GSLB Virtual Server with passive GSLB Service, and configure as Backup Virtual Server.
  3. Create CNAME records for each delegated DNS name – in the main DNS zone, create a CNAME that maps the original DNS name to the delegated sub-zone. For example, CNAME citrix.company.com to citrix.gslb.company.com.

You will create separate GSLB Services, separate GSLB Virtual Servers, and separate CNAMEs for each DNS name. If you have a bunch of DNS names that you want to GSLB-enable, then you’ll repeat these steps for each GSLB-enabled DNS name.

Each datacenter has a separate ADNS listener IP address. DNS is delegated to all GSLB ADNS Listener IPs, and any one of them can respond to the DNS query. Thus, all NetScaler pairs participating in GSLB should have the same Per-DNS name configuration.

One NetScaler appliance for both public DNS/GSLB and internal DNS/GSLB?

GSLB can be enabled both publically and internally. For public GSLB, configure it on DMZ NetScaler appliances, and expose the DNS listener to the Internet. For internal GSLB, configure it on separate internal NetScaler appliances/instances, and create an internal DNS listener.

Each NetScaler appliance only has one DNS table, so if you try to use the same NetScaler for both public DNS and internal DNS, then be aware that external users can query for internal GSLB-enabled DNS names.

  • As described by Phil Bossman in the comments, you can use a Responder policy to prevent external users from reading internal DNS names.
    add policy patset GSLB_INTERNAL
    bind policy patset GSLB_INTERNAL internalHostname.gslb.domain.com -index 1
    add responder action DNS_Empty_Response respondwith DNS.NEW_RESPONSE
    add responder policy GSLB_DNS_Empty_Response "(!(CLIENT.IP.SRC.IN_SUBNET(10.0.0.0/8)||CLIENT.IP.SRC.IN_SUBNET(192.0.0.0/16)||CLIENT.IP.SRC.IN_SUBNET(172.0.0.0/12)) && DNS.REQ.QUESTION.DOMAIN.CONTAINS_ANY(\"GSLB_INTERNAL\"))" DNS_Empty_Response
    bind responder global GSLB_DNS_Empty_Response 100 END -type DNS_REQ_DEFAULT

One appliance resolving a single DNS name differently for internal and public

Let’s say you have a single DNS name citrix.company.com. When somebody external resolves the name, it should resolve to a public IP. When somebody internal resolves the name, it should resolve to an internal IP.

For internal GSLB and external GSLB of the same DNS name on the same NetScaler appliance, you can use DNS Policies and DNS Views to return different IP addresses depending on where users are connecting from. See Citrix CTX130163 How to Configure a GSLB Setup for Internal and External Users Using the Same Host Name.

If the Internet circuit in the remote datacenter goes down, then this should affect public DNS, since you don’t want to give out a public IP that isn’t reachable. But do you also want an Internet outage to affect internal DNS? Probably not. In that case, you would need different GSLB monitoring configurations for internal DNS and external DNS. However, if you have only a single GSLB Virtual Server with DNS Views, then you can’t configure different monitoring configurations for each DNS View.

To work around this limitation, create two separate GSLB Virtual Servers with different monitoring configurations. Internal DNS uses a CNAME record to reach the GSLB Virtual Server configured for internal monitoring:

  • External citrix.company.com:
    • Configure NetScaler GSLB for citrix.company.com.
    • On public DNS, delegate citrix.company.com to the NetScaler DMZ ADNS services.
  • Internal citrix.company.com:
    • Configure NetScaler GSLB for citrixinternal.company.com or something like that.
    • On internal DNS, create CNAME for citrix.company.com to citrixinternal.company.com
    • On internal DNS, delegate citrixinternal.company.com to NetScaler internal ADNS services.

Remote Internet Monitoring

For public DNS/GSLB, you don’t want to give out a remote public IP address if that remote public IP address is not reachable. That means the local NetScaler will need to somehow determine if the remote datacenter has Internet connectivity or not. Here are some methods of verifying the remote Internet connection:

  • Route GSLB Metric Exchange Protocol (MEP) across the Internet. If MEP goes down, then all IP addresses associated with the remote GSLB Site are assumed to be down, and thus the local NetScaler will stop giving out those remote IP addresses.
  • Bind explicit monitors to each GSLB Service, and ensure the monitoring is routed across the Internet.

GSLB IP Addresses

GSLB is separate from data traffic. The GSLB IP addresses are separate from the IP addresses needed for data.

Some GSLB-specific IP Addresses are needed on each NetScaler pair:

  • ADNS Listener IP: A NetScaler IP that listens for DNS queries.
    • The ADNS listener IP is typically an existing SNIP on the appliance.
    • For external DNS, create a public IP for the ADNS Listener IP, and open UDP 53, so Internet-based DNS servers can access it.
    • A single NetScaler appliance can have multiple ADNS listeners – typically one ADNS listener for public, and another ADNS listener for internal.
  • GSLB Site IP / MEP listener IP: A NetScaler IP that will be used for NetScaler-to-NetScaler GSLB communication. This communication is called MEP or Metric Exchange Protocol. MEP transmits the following between GSLB-enabled NetScaler pairs: load balancing metrics, proximity, persistence, and monitoring.
    • GSLB Sites – On NetScaler, you create GSLB Sites. GSLB Sites are the endpoints for the MEP communication. Each NetScaler pair is configured with the MEP endpoints for the local appliance pair, and all remote appliance pairs.
    • TCP Ports – MEP uses port TCP 3009 or TCP 3011 between the NetScaler pairs. TCP 3009 is encrypted.
    • The ADNS IP address can be used as the MEP endpoint IP.
    • MEP endpoint can be any IP – The MEP endpoint IP address can be any IP address and does not need to be a SNIP or ADNS.
    • One MEP IP per appliance – there can only be one MEP endpoint IP address on each NetScaler pair.
    • Route MEP across Internet? – If you route MEP across the Internet, and if the MEP connection is interrupted, then Internet at one of the locations is probably not working. This is an easy way to determine if remote Internet is up or not. If you don’t route MEP across the Internet, then you’ll need to configure every remote-site GSLB Service with a monitor to ensure that the remote Internet is up.
      • Public IPs for MEP Enpoints – if you route MEP across the Internet, then you’ll need public IPs for each publically-accessible MEP endpoint IP address.
      • Public Port for MEP: Open port TCP 3009 between the MEP Public IPs. Make sure only the MEP IPs can access this port on the other NetScaler. Do not allow any other device on the Internet to access this port. Port 3009 is encrypted.
    • GSLB Sync Ports: To use GSLB Configuration Sync, open ports TCP 22 and TCP 3008 (secure) from the NSIP (management IP) to the remote public MEP IP. The GSLB Sync command runs a script in BSD shell and thus NSIP is always the Source IP.
  • Public IP Summary: In summary, for public GSLB, if MEP and ADNS are listening on the same IP, then you need one new public IP that is NAT’d to the DMZ IP that is used for ADNS and MEP (GSLB Site IP).
    • Each datacenter has a separate public IP.
    • DNS is delegated to all public ADNS IP listeners.

GSLB Wizard

NetScaler 12 has a GSLB Wizard at Traffic Management > GSLB.

However, the wizard is quite finicky (buggy?), and doesn’t really save any time or steps, so it won’t be documented here.

ADNS Listener

  1. At System > Network > IPs, identify a NetScaler-owned IP that you will use as the ADNS listener. This is typically a SNIP.
  2. Create a public IP for the ADNS Service IP, and configure firewall rules.
  3. On the left, expand Traffic Management > Load Balancing, and click Services.
  4. On the right, click Add.
  5. In the Basic Settings section, do the following:
    1. Name the service ADNS or similar.
    2. In the IP Address field, enter an appliance SNIP.
    3. In the Protocol drop-down, select ADNS.
  6. Click OK.
  7. Scroll down, and click Done to close the Load Balancing Service properties.
  8. On the left of the console, expand System, expand Network, and then click IPs.
  9. On the right, you’ll see the SNIP is now marked as the ADNS svc IP.
  10. Repeat the ADNS configuration on the other appliance pair in the other datacenter.
  11. Your NetScaler appliances are now DNS servers.

DNS Security

  1. NetScaler includes DNS Security Options, at Security > DNS Security, which can protect your ADNS service.
  2. To protect ADNS, set the Profile to All DNS Endpoints.

Metric Exchange Protocol

This section details MEP configuration between two GSLB Sites. See Citrix Docs for larger Parent-Child Topology Deployment Using the MEP Protocol.

GSLB Sites

  1. The local GSLB Site IP can be any IP. Or you can use the same SNIP, and same public IP, used for ADNS.
  2. Open the firewall rules for Metric Exchange Protocol.
  3. On the left, expand Traffic Management, right-click GSLB, and enable the feature.
  4. Expand GSLB, and click Sites.
  5. On the right, click Add.
  6. In the Create GSLB Site page, do the following:
    1. We’re adding the local site first. Enter a descriptive name for the local site.
    2. In the Site Type drop-down, select LOCAL.
    3. In the Site IP Address field, enter an IP that this appliance will listen for MEP traffic. This is typically a DMZ SNIP.
    4. For Internet-routed GSLB MEP, in the Public IP Address field, enter the public IP that is NAT’d to the GSLB Site IP.
    5. For internal GSLB MEP, there is no need to enter anything in the Public IP field.
  7. Scroll down, and click Create, to close the Create GSLB Site page.
  8. Go back to System > Network > IPs, and verify that the IP is now marked as a GSLB site IP.
  9. If you want to use the GSLB Sync Config feature, then you’ll need to edit the GSLB site IP, and enable Management Access.

    1. Scroll down, and enable Management Access. SSH is all you need.
  10. Go to the other appliance pair, and also create the Local GSLB site using its GSLB site IP, and its public IP that is NAT’d to the GSLB site IP.

    1. In System > Network > IPs on the remote appliance, there should now be a GSLB site IP. If GSLB Sync is desired, enable management access on that IP and ensure SSH is enabled.
  11. Now on each appliance, add another GSLB Site, which will be the Remote GSLB site.
  12. In the Create GSLB Site page, do the following:
    1. Enter a descriptive name for the remote site.
    2. Select REMOTE as the Type.
    3. Enter the other appliance’s actual GSLB Site IP as configured on the appliance. This IP does not need to be reachable.
    4. In the Public IP Address field, enter the public IP that is NAT’d to the GSLB Site IP on the other appliance. For MEP, TCP 3009 must be open from the local GSLB Site IP, to the remote public Site IP. For GSLB sync, TCP 22, and TCP 3008, must be open from the local NSIP, to the remote public Site IP.
  13. Click Create.
  14. Repeat on the other appliance.

RPC

MEP defaults to unencrypted on TCP 3011. To fix that:

  1. On the left, expand System, expand Network, and click RPC.
  2. On the right, right-click the new RPC address (the other site’s GSLB Site IP), and click Edit.
  3. On the bottom, check the box next to Secure.

    • If your local GSLB Site IP is not a SNIP, then you’ll need to change the RPC Node to use the local GSLB Site IP as the source IP. In the Source IP Address field, enter the local GSLB Site IP.
  4. Click OK when done.
  5. Do the same thing on the other appliance.
  6. If you go back to GSLB > Sites, you should see it as active.

If your MEP connection between GSLB Sites flaps, it might be useful to introduce a delay before remote GSLB Services are marked as Down.

  1. You can do this at Traffic Management > GSLB > Dashboard.
  2. On the right, click Change GSLB settings.
  3. In the GSLB Service State Delay Time (secs) field, enter a delay before the GSLB Services are marked as down when MEP goes down.

    set gslb parameter -GSLBSvcStateDelayTime 15

Static Proximity Geo Location Database

If you want to use DNS Policies, or Static Proximity GSLB Load Balancing, or Responders based on user’s location, import a geo location database.

NetScaler has a built-in database at /var/netscaler/inbuilt_db/ that you can use. Or you can download a database. Common free databases are:

For IP2Location, see the blog post Add IP2Location Database as NetScaler’s Location File for instructions on how to import.

Import the Built-in Geo database:

  1. In the NetScaler GUI, on the left, expand Traffic Management, expand GSLB, expand Database and Entries, and click Static Databases.
  2. On the right, click Add.
  3. Change the Import From selection to File.
  4. Click Choose File.
  5. Browse to /var/netscaler/inbuilt_db/, and open Citrix_NetScaler_InBuilt_GeoIP_DB.csv. To browse to the directory, select var, and then click Open. Repeat for each directory until you reach /var/netscaler/inbuilt_db.
  6. In the Location Format field, if using the built-in database, select netscaler, and click Create.
  7. When you open a GSLB Service, the public IP will be translated to a location.

Private IP Blocks

Geo Location databases only contain entries for Public IPs. For Private IPs, do the following:

  1. On the left, expand Traffic Management, expand GSLB, expand Database and Entries, and click Custom Entries.
  2. On the right, click Add.
  3. Enter a range of IP addresses for a particular location.
  4. Enter a Location Name in Geo Location format, which is typically six location words separated by periods. You can look in the static proximity database for examples.
  5. Click Create.
  6. Continue creating Custom Entries for other private IP blocks.

Use Geo Locations

You can use the Geo locations in a DNS Policy, static proximity GSLB Load Balancing, or Responders:

GSLB Services

GSLB Services represent the IP addresses that are returned in DNS Responses. The IP addresses represented by GSLB Services do not need to be on a NetScaler, but NetScaler-owned IP addresses (e.g. load balancing VIPs) have additional GSLB Site Persistence options (e.g. cookie-based persistence).

  • Each potential IP address in a DNS response is a separate GSLB Service.
  • GSLB Services are associated with GSLB Sites.
  • GSLB Service configuration is identical for active/active and active/passive. GSLB Virtual Server define active/active or active/passive, not GSLB Services.

GSLB should be configured identically on all NetScaler pairs that are responding to DNS queries. Since you have no control over which NetScaler will receive the DNS query, you must ensure that both NetScaler pairs are giving out the same DNS responses.

To create a GSLB Service:

  1. On the left, expand Traffic Management > GSLB, and click Services.
  2. On the right, click Add.
  3. The service name should be similar to the DNS name that you are trying to GSLB. Include the site name in the service name.
  4. Select one of the GSLB Sites. The IP address you’re configuring in this GSLB Service should be geographically located in the selected GSLB Site.
  5. On the bottom part, if the IP address is owned by this NetScaler, then select Virtual Servers, and select a Virtual Server that is already defined on this appliance. It should automatically fill in the other fields. This option is only available when creating a GSLB Service in the Local GSLB Site.

    1. If the IP address is not owned by this NetScaler, then change the selection to New Server, and enter the remote IP address in the Server IP field.
    2. The Server IP field is the IP address that NetScaler will monitor for reachability.
    3. If the remote IP is owned by a different NetScaler that is reachable by MEP, then enter the actual VIP configured on that remote NetScaler. The Server IP does not need to match what is returned to the DNS Query.
  6. In the Public IP field, enter the IP address that will be returned to the DNS Query. If you leave Public IP blank, then NetScaler will copy the Server IP to the Public IP field. For Public GSLB, the Public IP field is usually a Public IP address. For internal GSLB, the Public IP field is usually an internal IP, and probably matches the Server IP.
  7. Scroll up, and make sure the Service Type is SSL. It’s annoying that NetScaler doesn’t set this drop-down correctly.
  8. Scroll down, and click OK, to close the Basic Settings section.
  9. GSLB Service Monitoring – on the right, in the Advanced Settings column, you can click Monitors to bind a monitor to this GSLB Service. Review the following notes before you bind a monitor.

    • Local NetScaler VIP – If the GSLB Service IP is a VIP on the local appliance, then GSLB will simply use the state of the local traffic Virtual Server (Load Balancing, Content Switching, or Gateway). There’s no need to bind a monitor to the GSLB Service.
    • Remote NetScaler VIP – If the GSLB Service IP is a VIP on a remote appliance, then GSLB will use MEP to ask the other appliance for the state of the remote traffic Virtual Server. In both cases. There’s no need to bind a monitor to the GSLB Service.
    • GSLB Monitor overrides other Monitoring methods – If you bind a monitor to the GSLB Service, then MEP and local Virtual Server state are ignored (overridden).
    • Here are some reasons for binding a monitor to the GSLB Service:
      • IP is not on a NetScaler – If the GSLB Service IP is not hosted on a NetScaler, then only GSLB Service monitors can determine if the Service IP is up or not.
      • Monitor remote Internet – For Public DNS, if MEP is not routed through the Internet, then you need some method of determining if the remote Internet circuit is up or not. In that case, you’ll need to bind monitors directly to the GSLB Service. The route of the Monitor should go across the Internet. Or you can ping the Internet router in the remote datacenter to make sure it’s reachable.
      • Traffic Domains – If the GSLB Service IP is in a non-default Traffic Domain, then you will need to attach a monitor, since GSLB cannot determine the state of Virtual Servers in non-default Traffic Domains.
  10. Active/Active Site Persistence – If you intend to do GSLB active/active, and if you need site persistence, then you can configure your GSLB Services to use Connection Proxy or HTTP Redirect. See Citrix Blog Post Troubleshooting GSLB Persistence with Fiddler for more details. This only works with GSLB Service IPs that match Virtual Server VIPs on NetScaler appliances reachable through MEP.
  11. Scroll down, and click Done, to finish creating the GSLB Service.
  12. Create additional GSLB Services for each IP address that will be returned to a DNS query.

Manually Synchronize GSLB Configuration

Copy the GSLB Service Configuration to the remote NetScaler pair. You can either repeat the GUI steps listed above. Or you can do the following:

  1. On the left, expand Traffic Management, expand GSLB, and click Dashboard.
  2. On the right, click View GSLB Configuration.
  3. This shows you all of the CLI commands for GSLB. Look for add gslb service commands. You can copy them, and run them (SSH) on other NetScaler pairs that are participating in GSLB.

GSLB Virtual Server

The GSLB Virtual Server is the entity that the DNS name is bound to. GSLB Virtual Server then gives out the IP address of one of the GSLB Services that is bound to it.

For Active/Passive GSLB:

  1. Create a GSLB Virtual Server for the Passive IP address.
    1. Bind the Passive GSLB Service to the Passive GSLB Virtual Server.
  2. Create another GSLB Virtual Server for the Active IP address.
    1. Bind the Active GSLB Service to the Active GSLB Virtual Server.
    2. Configure Backup Virtual Server pointing to the Passive GSLB Virtual Server.
    3. Bind a DNS name to the Active GSLB Virtual Server.
  3. Repeat the GSLB Virtual Server configuration on other NetScaler pairs participating in GSLB.
  4. Delegate the DNS name to NetScaler ADNS.

For Active/Active GSLB:

  1. Create one GSLB Virtual Server.
    1. Bind two or more GSLB Services to the Virtual Server.
    2. Configure the GSLB Virtual Server Load Balancing Method – e.g. Proximity
    3. Configure Site Persistence:
      1. Source IP persistence is configured on the GSLB Virtual Server.
      2. Cookie Persistence is configured on the GSLB Services.
    4. Bind a DNS name to the GSLB Virtual Server.
  2. Repeat the GSLB Virtual Server configuration on other NetScaler pairs participating in GSLB.
  3. Delegate the DNS name to NetScaler ADNS.

Configure Active/Passive GSLB

Passive Virtual Server

  1. On the left, expand Traffic Management, expand GLSB, and click Virtual Servers.
  2. On the right, click Add.
  3. In the Basic Settings section, do the following:
    1. Give the Passive GSLB Virtual Server a descriptive name.
    2. Set the Service Type to SSL to match the GSLB Services that you will bind to this Virtual Server.
  4. Click OK to close the Basic Settings section.
  5. On the left, click where it says No GSLB Virtual Server to GSLBService Binding.

    1. Click where it says Click to select.
    2. Check the box next to an existing Passive GSLB Service, and click Select.
    3. Click Bind.
  6. Click OK to close the GSLB Virtual Server GSLB Service Binding section.
  7. Click OK to close the GSLB Virtual Server Domain Binding section. The DNS name is bound to the Active Virtual Server, not the Passive Virtual Sever.
  8. Click OK to close the ADNS Service section.
  9. Click Done to finish creating the Passive GLSB Virtual Server.

Active Virtual Server

  1. On the left, expand Traffic Management, expand GLSB, and click Virtual Servers.
  2. On the right, click Add.
  3. In the Basic Settings section, do the following:
    1. Give the Active GSLB Virtual Server a descriptive name.
    2. Set the Service Type to SSL to match the GSLB Services that you will bind to this Virtual Server.
  4. Click OK to close the Basic Settings section.
  5. On the left, click where it says No GSLB Virtual Server to GSLBService Binding.

    1. Click where it says Click to select.
    2. Check the box next to an existing Active GSLB Service, and click Select.
    3. Click Bind.
  6. Click OK to close the GSLB Virtual Server GSLB Service Binding section.
  7. On the left, click where it says No GSLB Virtual Server Domain Binding.
  8. In the Domain Binding page, do the following:
    1. Enter the FQDN that GSLB will resolve.
    2. Click Bind.
  9. Click OK to close the GSLB Virtual Server Domain Binding section.
  10. Click OK to close the ADNS Service section.
  11. On the right, in the Advanced Settings section, click Backup Virtual Server to add it to the left.
  12. On the left, in the Backup Virtual Server section, select the Passive GSLB Virtual Server, and click OK.
  13. Click Done when done creating the Active GSLB Virtual Server.
  14. On the left, if you expand Traffic Management > DNS, expand Records, and click Address Records
  15. You’ll see a new DNS record for the GSLB domain you just configured. Notice it is marked as GSLB DOMAIN, and has a default TTL of 5 seconds. You can also see which GSLB Virtual Server it is bound to.
  16. Configure identical GSLB Virtual Servers on the other NetScaler appliance pair. Both NetScaler pairs must be configured identically. You can use Traffic Management > GSLB > Dashboard > View GSLB Configuration to copy the add/set/bind gslb vserver commands from this appliance to other NetScaler appliances.

Configure Active/Active GSLB

  1. On the left, expand Traffic Management, expand GLSB, and click Virtual Servers.
  2. On the right, click Add.
  3. In the Basic Settings section, do the following:
    1. Give the GSLB Virtual Server a descriptive name.
    2. Set the Service Type to SSL to match the GSLB Sevices you intend to bind.
    3. You can optionally check the box for Send all “active” service IPs in response (MIR). By default, GSLB only gives out one IP address per DNS query. This checkbox always returns all IPs, but the IPs are ordered based on the GSLB Load Balancing Method and/or GSLB Persistence.
    4. A new DNS feature called ECS will contain the actual DNS client IP. This dramatically improves the accuracy of determining a user’s location. Without this setting, GSLB can only see the IP address of the user’s configured DNS server instead of the real client IP. Check the box next to Respond with ECS option to enable ECS for site persistence.

      set gslb vserver <gslb_vserver> -ECS ENABLED
  4. Click OK to close the Basic Settings section.
  5. On the left, click where it says No GSLB Virtual Server to GSLBService Binding.

    1. Click where it says Click to select.
    2. Check the boxes next to multiple existing GSLB Services, and click Select.
    3. Click Bind.
  6. Click OK to close the GSLB Virtual Server GSLB Service Binding section.
  7. On the left, click where it says No GSLB Virtual Server Domain Binding.

    1. Enter the FQDN that this GSLB Virtual Server will resolve.
    2. Click Bind.
  8. Click OK to close the GSLB Virtual Server Domain Binding section.
  9. Click OK to close the ADNS Service section.
  10. On the left, in the Method section, click the pencil icon.

    1. Change the Choose Method drop-down to Static Proximity or similar. This assumes the Geo Location database has already been installed on the appliance.
    2. Click OK to close the Method section.
  11. On the right, in the Advanced Settings column, click Persistence to add it to the left.

    1. Change the Persistence drop-down to Source IP.
    2. Enter a Persistence Id.
      1. This ID must match on every NetScaler pair participating in GSLB.
      2. Each active/active GSLB Virtual Server should have a different Persistence ID.
    3. In the Time-out field, enter the Persistence Time-out. This is typically the same or longer than the webpage timeout.
    4. Click OK to close the Persistence section.
  12. Click Done to finish creating the GSLB Virtual Server.
  13. On the left, if you expand Traffic Management > DNS, expand Records, and click Address Records
  14. You’ll see a new DNS record for the GSLB domain you just configured. Notice it is marked as GSLB DOMAIN, and has a default TTL of 5 seconds. You can also see which GSLB Virtual Server it is bound to.
  15. Configure an identical GSLB Virtual Server on the other NetScaler appliance pair. Both NetScaler pairs must be configured identically. You can use Traffic Management > GSLB > Dashboard > View GSLB Configuration to copy the add/set/bind gslb vserver commands from this appliance to other NetScaler appliances.


GSLB Configuration Synchronization Script

Manual GSLB Synchronization

  1. The script requires SSH to be enabled on your GSLB Site IPs.

  2. Ports TCP 3008, TCP 3010, and TCP 22 must be opened from the local NSIP to the remote GSLB Site IP.
  3. To manually run the script that syncs GSLB configuration from one GSLB Site to another, on the left, expand Traffic Management, expand GSLB, and click Dashboard.
  4. On the right, click Auto Synchronization GSLB.
  5. Use the check boxes on the top, if desired. It’s usually a good idea to Preview the changes before applying them.
  6. Then click Run to begin synchronization.
  7. Click Close.
  8. You can Run it again without previewing it. It seems to take several seconds to complete.

Automatic GSLB Synchronization

  1. There is an automatic GSLB Configuration Sync feature, which automatically syncs the GSLB config every 15 seconds. To enable it on the master appliance, go to Traffic Management > GSLB > Dashboard. On the right, click Change GSLB settings.
  2. Check the box next to Automatic Config Sync. Only enable this on the one appliance where you are configuring GSLB, and want that GSLB config synced to other appliance.
  3. The automatic sync log can be found at /var/netscaler/gslb/periodic_sync.log.

Some notes regarding GSLB Sync:

  • When syncing GSLB Services, it tries to create Load Balancing Server objects on the remote appliance. If the GSLB Service IP matches an existing Load Balancing Server object, then the GSLB sync will fail. Check the Sync logs for details. You’ll have to delete the conflicting Load Balancing Server object before GSLB Sync works correctly.
  • GSLB Sync runs as a script on the BSD shell and thus always uses the NSIP as the source IP.
  • GSLB Sync connects to the remote GSLB Site IP on TCP 3008 (if RPC is Secure) and TCP 22.

Test GSLB

  1. You can test GSLB DNS name resolution from the GUI by going to Traffic Management > GSLB > Dashboard, and on the right, click Test GSLB.

  2. Select a GSLB Domain Name.
  3. Select an ADNS Service IP to test it from, and click Test.
  4. The test performs a dig against the ADNS IP. Verify that the response contains the IP address you expected.
  5. Another method of testing GSLB is to simply point nslookup to the ADNS services, and submit a DNS query for one of the DNS names bound to a GSLB vServer. Run the query multiple times to make sure you’re getting the response you expect.
  6. The NetScaler ADNS services at both GSLB sites should be giving the same response.
  7. To simulate a failure, if the GSLB Service IP is a NetScaler Traffic Management or Gateway IP, you can disable the Traffic Management or Gateway Virtual Server.
  8. Then the responses should change. Verify on both ADNS services.
  9. Re-enable the traffic Virtual Server, and the responses should return to normal.

DNS Delegation

If you are enabling GSLB for the domain gateway.corp.com, you’ll need to create a delegation at the server that is hosting the corp.com DNS zone. For public GSLB, you need to edit the public DNS zone for corp.com.

DNS Delegation instructions will vary depending on what product host’s the public DNS zone. This section details Microsoft DNS, but it should be similar in BIND or web-based DNS products.

There are two ways to delegate GSLB-enabled DNS names to NetScaler ADNS:

  • Delegate the individual record. For example, delegate gateway.corp.com to the two NetScaler ADNS services (gslb1.corp.com and gslb2.corp.com).
  • Delegate an entire subzone. For example, delegate the subzone gslb.corp.com to the two NetScaler ADNS services. Then create a CNAME record in the parent DNS zone for gateway.corp.com that is aliased to gateway.gslb.corp.com. When DNS queries make it to NetScaler, they will be for gateway.gslb.corp.com and thus gateway.gslb.corp.com needs to be bound to the GSLB Virtual Server instead of gateway.corp.com. For additional delegations, simply create more CNAME records.

Delegate an individual DNS record

  1. Run DNS Manager.
  2. First, create Host Records pointing to the ADNS services running on the NetScaler pairs in each data center. These host records for ADNS are used for all GSLB delegations no matter how many GSLB delegations you need to create. These are sometimes called glue records.
  3. The first Host record is gslb1, (or similar) and should point to the ADNS service (Public IP) on one of the NetScaler appliances.
  4. The second Host record is gslb2, and should point to the ADNS Service (public IP) on the other NetScaler appliance.
  5. If you currently have a host record for the service that you are delegating to GSLB (gateway.corp.com), delete it.
  6. Right-click the parent DNS zone, and click New Delegation.
  7. In the Welcome to the New Delegation Wizard page, click Next.
  8. In the Delegated Domain Name page, enter the left part of the DNS record that you are delegating (e.g. gateway for gateway.corp.com). Click Next.
  9. In the Name Servers page, click Add.
  10. This is where you specify gslb1.corp.com and gslb2.corp.com as delegated name servers. Enter gslb1.corp.com, and click Resolve. Then click OK. If you see a message about the server not being authoritative for the zone, ignore the message. Note: you only add one name server at a time.
  11. Then click Add to add the other GSLB ADNS server.
  12. Once both ADNS servers are added to the list, click Next.
  13. In the Completing the New Delegation Wizard page, click Finish.
  14. The delegation is shown in the DNS Manager console.
  15. If you run nslookup against your Microsoft DNS server, it will respond with Non-authoritative answer. That’s because it got the response from NetScaler, and not from itself.

Delegate a Sub-zone

  1. Run DNS Manager.
  2. First, create Host Records pointing to the ADNS services running on the NetScaler pairs in each data center. These are sometimes called glue records.
  3. The first Host record is gslb1 (or similar), and should point to the ADNS service (Public IP) on one of the NetScaler appliances.
  4. The second Host record is gslb2, and should point to the ADNS Service (public IP) on the other NetScaler appliance.
  5. Right-click the parent DNS zone, and click New Delegation.
  6. In the Welcome to the New Delegation Wizard page, click Next.
  7. In the Delegated Domain Name page, enter the left part of the DNS sub-zone that you are delegating (e.g. gslb for gslb.corp.com). Click Next.
  8. In the Name Servers page, click Add.
  9. This is where you specify gslb1.corp.com and gslb2.corp.com. Enter gslb1.corp.com, and click Resolve. Then click OK. If you see a message about the server not being authoritative for the zone, ignore the message. Note: you only add one name server at a time.
  10. Then click Add to add the other GSLB ADNS server.
  11. Once both ADNS servers are added to the list, click Next.
  12. In the Completing the New Delegation Wizard page, click Finish.
  13. The sub-zone delegation is shown in the DNS Manager console.

Each GSLB-enabled DNS name must be CNAMED to GSLB:

  1. In NetScaler, go to Traffic Management > GSLB > Virtual Servers, and edit your GSLB Virtual Server.
  2. On the left, click in the GSLB Virtual Server Domain Binding section.
  3. Click Add Binding.
  4. Add a domain binding for the CNAMED DNS name. For example, if the original DNS name is gateway.corp.com, then enter gateway.gslb.corp.com. gslb.corp.com matches the sub-zone that you delegated to NetScaler. Click OK.
  5. Repeat the Domain Binding on the other NetScaler appliances.
  6. In DNS Manager, if you currently have a host record for the service that you are delegating to GSLB (gateway.corp.com), delete it.
  7. Right-click the DNS zone, and click New Alias (CNAME).
  8. In the Alias name field, enter the left part of the original DNS name. For gateway.corp.com, enter gateway.
  9. In the Fully qualified domain name (FQDN) for target host field, enter the CNAMED DNS name that is delegated to NetScaler. For example, if you delegated gslb.corp.com to NetScaler, then enter gateway.gslb.corp.com. The GSLB Virtual Server must be configured to match this longer DNS name.
  10. Click OK.
  11. If you run nslookup for the delegated DNS name, it will first CNAME to the longer name, and then respond with the IP address returned by NetScaler GSLB.
  12. You can repeat these steps to delegate (CNAME) additional DNS names to NetScaler GSLB.

NetScaler Gateway 12 RADIUS Authentication

Last Modified: Aug 23, 2017 @ 11:34 am

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RADIUS Overview

One method of two-factor authentication to NetScaler Gateway is the RADIUS protocol with a two-factor authentication product (tokens) that has RADIUS enabled.

RADIUS Clients and Source IP – On your RADIUS servers, you’ll need to add the NetScaler appliances as RADIUS Clients. When NetScaler uses a local (same appliance) load balanced Virtual Server for RADIUS authentication, the traffic is sourced from the NetScaler SNIP (Subnet IP). When NetScaler uses a direct connection to a RADIUS Server without going through a load balancing Virtual Server, or uses a remote (different appliance) Load Balancing Virtual Server, the traffic is sourced from the NetScaler NSIP (NetScaler IP). Use the correct IP(s) when adding the NetScaler appliances as RADIUS Clients. And adjust firewall rules accordingly.

  • For High Availability pairs, if you locally load balance RADIUS, then you only need to add the SNIP as a RADIUS Client, since the SNIP floats between the two appliances. However, if you are not locally load balancing RADIUS, then you’ll need to add the NSIP of both appliances as RADIUS Clients. Use the same RADIUS Secret for both appliances.

Links:

Some two-factor products (e.g. SMS Passcode) require you to hide the 2nd password field. Receiver 4.4 and newer supports hiding the 2nd field if you configure a Meta tag in index.html.

Two-factor Policies Summary

NetScaler has two methods of multi-factor:

  • NetScaler Gateway Virtual Server has bind points for Primary and Secondary authentication. This functionality is available in all NetScaler Editions and is detailed in this post.
  • nFactor Authentication supports unlimited factors, but requires NetScaler Enterprise Edition or NetScaler Platinum Edition.

See the NetScaler 12 page for additional authentication mechanisms supported by NetScaler 12. Some require nFactor.

When configuring the NetScaler Gateway Virtual Server, you can specify both a Primary authentication policy, and a Secondary authentication policy. Users are required to successfully authenticate against both policies before being authorized for NetScaler Gateway.

For browser-based StoreFront, you need two authentication policies:

  • Primary = LDAPS authentication policy pointing to Active Directory Domain Controllers.
  • Secondary = RADIUS authentication policy pointing to RSA servers with RADIUS enabled.

For Receiver Self-service (native Receiver on mobile, Windows, and Mac), the authentication policies are swapped:

  • Primary = RADIUS authentication policy pointing to RSA servers with RADIUS enabled.
  • Secondary = LDAPS authentication policy pointing to Active Directory Domain Controllers.

If you need to support two-factor authentication from both web browsers and Receiver Self-Service, then you’ll need at least four authentication policies as shown below.

Primary:

  • Priority 90 = RADIUS policy. Expression = REQ.HTTP..HEADER User-Agent CONTAINS CitrixReceiver
  • Priority 100 = LDAP policy. Expression = REQ.HTTP..HEADER User-Agent NOTCONTAINS CitrixReceiver

Secondary:

  • Priority 90 = LDAP policy. Expression = REQ.HTTP..HEADER User-Agent CONTAINS CitrixReceiver
  • Priority 100 = RADIUS policy. Expression = REQ.HTTP..HEADER User-Agent NOTCONTAINS CitrixReceiver

Create Two-factor Policies

Create an LDAP Server/Action

See the LDAP post for instructions. Only the server/action is needed. The Policies will be created later.

Create a RADIUS Sever/Action

  1. On the left, expand Authentication, and click Dashboard.
  2. On the right, click Add.
  3. Change Choose Server Type to RADIUS.
  4. Give the server a name.
  5. Specify the IP address of the RADIUS load balancing Virtual Server.
  6. Enter the secret key specified when you added the NetScalers as RADIUS clients on the RADIUS server. Click Test Connection.
  7. Scroll down, and click Create.

    add authentication radiusAction RSA -serverIP 10.2.2.210 -serverPort 1812 -radKey Passw0rd

Create Authentication Policies for LDAP and RADIUS

  1. Since you can’t create authentication policies from the authentication dashboard, go to NetScaler Gateway > Policies > Authentication > RADIUS.
  2. On the right, in the Policies tab, click Add.
  3. Name it RSA-ReceiverSelfService or similar.
  4. Select the RADIUS server created earlier.
  5. Enter an expression. You will need two policies with different expressions. The expression for Receiver Self-Service is REQ.HTTP.HEADER User-Agent CONTAINS CitrixReceiver. Note: NetScaler 12 does not natively support Advanced Authentication Policies so you’ll have to create them as Basic Policies (classic expressions).
  6. Click Create.
  7. If you see a warning about deprecation, click OK, and ignore it.
  8. Create another RADIUS policy to match the ones shown below. Both RADIUS policies are configured with the same RADIUS server. The only difference between them is the expression (CONTAINS vs NOTCONTAINS):
    Name Expression Server
    RSA-ReceiverSelfService REQ.HTTP.HEADER User-Agent CONTAINS CitrixReceiver RSA
    RSA-ReceiverForWeb REQ.HTTP.HEADER User-Agent NOTCONTAINS CitrixReceiver RSA

  9. Go to the NetScaler Gateway\Policies\Authentication\LDAP node.
  10. On the Policies tab, create two policies with the expressions shown below. Both LDAP policies are configured with the same LDAP server. The only difference between them is the expression (CONTAINS vs NOTCONTAINS).
    Name Expression Server
    LDAP-Corp-ReceiverSelfService REQ.HTTP.HEADER User-Agent CONTAINS CitrixReceiver LDAP-Corp
    LDAP-Corp-ReceiverForWeb REQ.HTTP.HEADER User-Agent NOTCONTAINS CitrixReceiver LDAP-Corp

add authentication radiusPolicy RSA-ReceiverForWeb "REQ.HTTP.HEADER User-Agent NOTCONTAINS CitrixReceiver" RSA

add authentication radiusPolicy RSA-ReceiverSelfService "REQ.HTTP.HEADER User-Agent CONTAINS CitrixReceiver" RSA

add authentication ldapPolicy Corp-Gateway-ReceiverForWeb "REQ.HTTP.HEADER User-Agent NOTCONTAINS CitrixReceiver" Corp-Gateway

add authentication ldapPolicy Corp-Gateway-ReceiverSelfService "REQ.HTTP.HEADER User-Agent CONTAINS CitrixReceiver" Corp-Gateway

Bind Two-factor Policies to Gateway

  1. When you create or edit a NetScaler Gateway Virtual Server, bind the Basic Authentication Policies as shown in the following table. Priority doesn’t matter because they are mutually exclusive.
    Policy Name Type Bind Point
    LDAP-Corp-ReceiverForWeb LDAP Primary
    RSA-ReceiverSelfService RADIUS Primary
    LDAP-Corp-ReceiverSelfService LDAP Secondary
    RSA-ReceiverForWeb RADIUS Secondary

    bind vpn vserver gateway.corp.com -policy Corp-Gateway-ReceiverForWeb -priority 100
    
    bind vpn vserver gateway.corp.com -policy RSA-ReceiverSelfService -priority 110
    
    bind vpn vserver gateway.corp.com -policy RSA-ReceiverForWeb -priority 100 -secondary
    
    bind vpn vserver gateway.corp.com -policy Corp-Gateway-ReceiverSelfService -priority 110 -secondary
    
  2. The Session Policy/Profile for Receiver Self-Service needs to be adjusted to indicate which authentication field contains the Active Directory password. On the Client Experience tab is Credential Index. This needs to be changed to SECONDARY. Leave the session policy for Web Browsers set to Primary.

    set vpn sessionAction "Receiver Self-Service" -ssoCredential SECONDARY
  3. On the StoreFront server, when creating the NetScaler Gateway object, on the Authentication Settings page, change the Logon type to Domain and security token. This instructs Receiver to properly handle two-factor authentication. If you change this setting after Receiver has already performed discovery, then users might have to remove the Account from Receiver and re-add it.

RADIUS Load Balancing – NetScaler 12

Last Modified: Aug 23, 2017 @ 11:45 am

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RADIUS Load Balancing Overview

One method of two-factor authentication to NetScaler Gateway is the RADIUS protocol with a two-factor authentication product (tokens) that has RADIUS enabled.

RADIUS Clients and Source IP – On your RADIUS servers, you’ll need to add the NetScaler appliances as RADIUS Clients. When NetScaler uses a local (same appliance) load balanced Virtual Server for RADIUS authentication, the traffic is sourced from the NetScaler SNIP (Subnet IP). When NetScaler uses a direct connection to a RADIUS Server without going through a load balancing Virtual Server, or uses a remote (different appliance) Load Balancing Virtual Server, the traffic is sourced from the NetScaler NSIP (NetScaler IP). Use the correct IP(s) when adding the NetScaler appliances as RADIUS Clients. And adjust firewall rules accordingly.

  • For High Availability pairs, if you locally load balance RADIUS, then you only need to add the SNIP as a RADIUS Client, since the SNIP floats between the two appliances. However, if you are not locally load balancing RADIUS, then you’ll need to add the NSIP of both appliances as RADIUS Clients. Use the same RADIUS Secret for both appliances.

RADIUS Monitor and Static Credentials – When load balancing RADIUS, you’ll want a monitor that verifies that the RADIUS server is functional. The RADIUS monitor will login to the RADIUS server and look for a response. The credentials in the load balancing monitor must have a static password.

  • If you don’t mind failed login attempts in your RADIUS logs, you can specify fake credentials in your load balancing monitor. The monitor would be configured to expect a login failure response, which means that at least a RADIUS service is responding to the monitor. Not as accurate as a successful login response, but better than ping.
  • The only other monitoring option is Ping. No credentials needed for this option. Adjust the firewall to allow ping to the RADIUS servers.

Active/passive load balancing – If you have RADIUS Servers in multiple datacenters, you can create multiple load balancing Virtual Servers, and cascade them so that the local RADIUS Servers are used first, and if they’re not available, then the Virtual Server fails over to RADIUS Servers in remote datacenters.

RADIUS Monitor

The RADIUS Monitor attempts to successfully log into the RADIUS server. For RSA, create an account on RSA with the following parameters as mentioned by Jonathan Pitre:

  • Setup a user with a fixed passcode in your RSA console.
  • Ensure you login with that user at least once to the RSA console because you’ll be asked to change it the first time.
  • There is no need to assign a token to your monitor user as long as you are using a fixed passcode. You don’t want to waste a token on a user just for monitoring.

Henny Louwers – Configure RSA RADIUS monitoring on NetScaler:

  1. In the NetScaler Configuration Utility, on the left, under Traffic ManagementLoad Balancing, click Monitors.
  2. On the right, click Add.
  3. Name the monitor RSA or similar.
  4. Change the Type drop-down to RADIUS.
  5. On the Standard Parameters tab, you might have to increase the Response Time-out to 4.
  6. On the Special Parameters tab, do the following:
    1. Enter valid RADIUS credentials. Make sure these credentials do not change or expire. For RSA, in the Password field, enter the fixed passcode.
    2. Also enter the RADIUS key (secret) configured on the RADIUS server for the NetScaler as RADIUS client.
    3. For Response Codes, add both 2 and 32 means success, while 3 indicates some kind of failure. Either result means that the RADIUS server is responding, and thus is probably functional. But 2 is the ideal response.
  7. Click Create when done.

    add lb monitor RSA RADIUS -respCode 2-3 -userName ctxsvc -password Passw0rd -radKey Passw0rd -resptimeout 4

Servers

  1. On the left, expand Traffic Management, expand Load Balancing, and click Servers.
  2. On the right, click Add.
  3. Enter a descriptive server name; usually it matches the actual server name.
  4. Enter the IP address of the RADIUS server.
  5. Enter comments to describe the server. Click Create.

    add server RSA01 10.2.2.42
    add server RSA02 10.2.2.43
  6. Continue adding RADIUS servers.

Service Groups

  1. On the left, expand Traffic Management, expand Load Balancing, and click Service Groups.
  2. On the right, click Add.
  3. You will create one Service Group per datacenter. Enter a name reflecting the name of the datacenter.
  4. Change the Protocol to RADIUS.
  5. Scroll down, and click OK, to close the Basic Settings section.
  6. On the left, in the Service Group Members section, click where it says No Service Group Member.

    1. If you did not create server objects, then enter the IP address of a RADIUS Server in this datacenter. If you previously created a server object, then change the selection to Server Based, and select the server object(s).
    2. In the Port field, enter 1812 (RADIUS).
    3. Click Create.
  7. Click OK when done adding members.
  8. On the right, in the Advanced Settings column, click Monitors.

    1. On the left, in the Monitors section, click where it says No Service Group to Monitor Binding.
    2. Click where it says Click to select.
    3. Click the radio button next to your new RADIUS monitor, and click Select.
    4. Click Bind.
  9. To verify the members are up, click in the Service Group Members section.

    1. Right-click a member, and click Monitor Details.
    2. It should say Radius response code 2 (or 3) received. Click Close twice.
  10. Scroll down, and click Done to finish creating the Service Group.

    add serviceGroup svcgrp-RSA RADIUS
    bind serviceGroup svcgrp-RSA RSA01 1812
    bind serviceGroup svcgrp-RSA RSA02 1812
    bind serviceGroup svcgrp-RSA -monitorName RSA
  11. Add additional service groups for RADIUS servers in each data center.

Virtual Server

  1. On the left, expand Traffic Management, expand Load Balancing, and click Virtual Servers.
  2. On the right, click Add.
  3. In the Basic Settings section, do the following:
    1. Name it lbvip-RADIUS-HQ or similar. You will create one Virtual Server per datacenter so include the datacenter name.
    2. Change the Protocol drop-down to RADIUS.
    3. Enter a Virtual IP. This VIP cannot conflict with any other IP + Port already being used. You can use an existing VIP if the VIP is not already listening on UDP 1812.
    4. Enter 1812 as the Port.
  4. Click OK to close the Basic Settings section.
  5. In the Services and Service Groups section, click where it says No Load Balancing Virtual Server ServiceGroup Binding.

    1. Click where it says Click to select.
    2. Click the radio button next to a previously created Service Group, and click Select.
    3. Click Bind.
  6. Click Continue.
  7. On the right, in the Advanced Settings section, click Method.
  8. On the left, in the Method section, do the following:
    1. Change the Load Balancing Method to TOKEN.
    2. In the Expression box, enter CLIENT.UDP.RADIUS.USERNAME.
  9. Click OK to close the Method section.
  10. On the right, in the Advanced Settings section, click Persistence.
  11. On the left, in the Persistence section, do the following:
    1. Change Persistence to RULE.
    2. In the Expression box, enter CLIENT.UDP.RADIUS.USERNAME.
  12. Click OK to close the Persistence section.
  13. Scroll down and click Done to finish creating the Virtual Server.
  14. If you are configuring this RADIUS Load Balancer for more than just NetScaler Gateway, you can add another Load Balancer on port 1813 for RADIUS Accounting. Then you need a Persistency Group to tie the two load balancers together. See Configuring RADIUS Load Balancing with Persistence at Citrix Docs.
    add lb vserver lbvip-RSA RADIUS 10.2.2.210 1812 -persistenceType RULE -lbMethod TOKEN -rule CLIENT.UDP.RADIUS.USERNAME
    bind lb vserver lbvip-RSA svcgrp-RSA
  15. The new Virtual Server should show as Up. If not, click the Refresh icon.

Active/Passive Load Balancing

  1. Create additional Virtual Servers for each datacenter.

    1. These additional Virtual Servers do not need a VIP. so change the IP Address Type to Non Addressable. Only the first Virtual Server will be directly accessible.

      add lb vserver lbvip-RSA-Backup RADIUS 0.0.0.0 0 -persistenceType NONE -cltTimeout 120
    2. Notice that the additional datacenter Virtual Servers have an IP Address of 0.0.0.0 and port of 0.
  2. After you are done creating a Virtual Server for each datacenter, right-click the primary datacenter’s Virtual Server, and click Edit.
  3. On the right, in the Advanced Settings column, click Protection.
  4. On the left, in the Protection section, change the Backup Virtual Server to one of the other datacenter Virtual Servers. If all of the services in this datacenter are DOWN, the backup Virtual Server will be used instead. You can cascade multiple Virtual Servers using this method. Click OK and Done.

    set lb vserver lbvip-RSA -backupVServer lbvip-RSA-Backup
  5. You may now use this Virtual IP in your RADIUS authentication policies for NetScaler Gateway or NetScaler management login.

NetScaler Gateway 12 Tweaks

Last Modified: Sep 16, 2017 @ 11:33 am

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NetScaler Gateway Feature Licensing

Here is a listing of some NetScaler Gateway features and the licenses they require:

Feature NetScaler Editions Universal Licenses?
StoreFront Load Balancing Standard/Enterprise/Platinum
Global Server Load Balancing (GSLB) Enterprise/Platinum
ICA Proxy and StoreFront Proxy All
Two-factor Auth (RADIUS) All
StoreFrontAuth (nFactor) Enterprise/Platinum
nFactor Authentication Enterprise/Platinum
Native OTP Authentication (nFactor) Enterprise/Platinum
HDX Insight (AppFlow) Enterprise/Platinum
SmartAccess All Yes
SmartControl Platinum Yes
RDP Proxy Enterprise/Platinum Yes
SSL VPN All Yes
PCoIP Proxy Enterprise/Platinum Yes
Unified Gateway Enterprise/Platinum Yes
Citrix SCOM MP for NetScaler Platinum

All Editions = NetScaler Gateway Enterprise VPX, NetScaler Standard, NetScaler Enterprise, and NetScaler Platinum.

  • NetScaler Gateway Enterprise VPX is the cheap VPX appliance that only does NetScaler Gateway. It doesn’t even do Load Balancing.
  • NetScaler Enterprise Edition is the minimum edition for many Gateway features, and thus is recommended for all Gateway purchases.

Gateway Universal Licenses – many NetScaler Gateway features require NetScaler Gateway Universal licenses for each concurrent connection to the NetScaler Gateway Virtual Server. See the above table for which features require these licenses.

When you create a NetScaler Gateway Virtual Server, in the Basic Settings section, the ICA Only setting determines if you need NetScaler Gateway Universal licenses or not. If the Virtual Server is set to ICA Only is true, then features requiring Universal Licenses are disabled. But if ICA Only is set to false, then you need a NetScaler Gateway Universal license for every user that connects to this NetScaler Gateway Virtual Server.

Most editions of NetScaler include Universal licenses:

  • NetScaler Gateway Enterprise VPX does not come with any Gateway Universal Licenses
  • NetScaler Standard Edition comes with 500 Gateway Universal Licenses
  • NetScaler Enterprise Edition comes with 1,000 Gateway Universal Licenses
  • NetScaler Platinum Edition comes with unlimited Gateway Universal Licenses

If your NetScaler Edition does not include a sufficient number of Universal Licenses for your user load, then you can acquire these licenses through other means:

  • XenApp/XenDesktop Platinum Edition includes Gateway Universal licenses for each licensed user
  • XenMobile App Edition and XenMobile Enterprise Edition include Gateway Universal licenses for each licensed user
  • “a la carte” NetScaler Gateway Universal Licenses – these are very inexpensive

You can install more Gateway Universal licenses on the NetScaler appliance. The Gateway Universal licenses are allocated to the case sensitive hostname of each appliance. If you have an HA pair, and if each node has a different hostname, then allocate the Gateway Universal licenses to the first hostname, and then reallocate the same licenses to the other hostname.

To see the hostname, click your username on the top right.

To change the hostname:

  1. Click the gear icon on the top right.
  2. Then click the third section.

Go to mycitrix.com, and allocate your purchased Gateway Universal licenses to the hostname of the appliance.

To upload the allocated Gateway Universal licenses to the appliance, go to System > Licenses > Manage Licenses. A reboot is required.

To see the number of installed Gateway Universal licenses:

  1. On the left, expand System, and click Licenses.
  2. On the right, in the Maximum NetScaler Gateway Users Allowed field is the number of licensed users for NetScaler Gateway Virtual Servers that are not set to ICA Only.

RFWebUI Portal Theme

Citrix Blog Post Branding your Deployment Part 2: Matching NetScaler to StoreFront explains NetScaler Gateway Portal Themes, how to edit the Portal Theme CSS, and warns about GUI changes overwriting CSS file changes.

If you want the logon page for NetScaler Gateway to look more like StoreFront 3.0 and newer, enable the built-in RfWebUI or X1 theme. RfWebUI is optimized for Unified Gateway (Clientless VPN) since it provides the exact same appearance and user experience as StoreFront 3.x. The Unified Gateway RfWebUI theme can display RDP Links, Web Links (bookmarks), PCoIP published icons, along with the familiar StoreFront apps and desktops. Note: RfWebUI requires StoreFront 3.6 or newer.

  1. Go to NetScaler Gateway > Virtual Servers, and edit an existing Virtual Server.
  2. If you see the Portal Themes section on the left:
    • Then click the pencil icon.
  3. If you don’t see Portal Themes on the left:
    • On the right, in the Advanced Settings section, click Portal Themes.
  4. On the left, change the Portal Theme drop-down to RfWebUI. Click OK.
  5. Click Done.

    bind vpn vserver gateway.corp.com -portaltheme RfWebUI
  6. When you access the NetScaler Gateway login page you’ll see the theme.

Custom Portal Theme

You can create your own theme by starting from one of the built-in themes:

  1. Go to NetScaler Gateway > Portal Themes.
  2. On the right, click Add.
  3. Give the theme a name, select RfWebUI as the Template Theme, and click OK.
  4. In the Look and Feel section, there are two sub-sections: one for Home Page Attributes, and one for Common Attributes.
  5. The Home Page Attributes section is for Unified Gateway (aka VPN Clientless Access). Notice that the Websites Sections can be disabled.
  6. The Help Legend link at the top of the section shows you what the other fields modify.

  7. If you want to modify some attributes of the logon page, use the Common Attributes sub-section. The labels are changed later.
  8. The Help Legend link at the top of the Common Attributes section shows you what the fields modify.
  9. Make changes as desired, and click OK at the bottom of the page.
  10. After you click OK, the Language section appears.
  11. In the Language section, select a language, and click OK.
  12. On the right, in the Advanced Settings section, click Login Page.
  13. Make changes as desired (e.g. Password Field Titles), and click OK.
  14. At the top of the screen, click the link to Click to Bind and View Configured Theme.
  15. Select a Gateway Virtual Server, and click Bind and Preview. Notice that you can also bind Portal Themes to AAA vServers.
  16. The logon page is displayed.
  17. You could go to /var/netscaler/logon/themes/MyTheme/css and make more changes to custom.css, but this file gets overwritten any time you make a change in the Portal Themes section of the NetScaler GUI.
  18. Citrix CTX209526 NetScaler; How to Copy a Portal Theme from the Device running version 11.0 to another Device running 11.0.

Public DNS SRV Records

When a user launches Receiver, instead of typing in the Gateway FQDN, the user can enter an email address. Receiver uses the email suffix to lookup the Gateway FQDN. It does this by looking for an SRV record named _citrixreceiver._tcp in the email suffix’s domain (e.g. _citrixreceiver._tcp.corp.com). If you have multiple email suffixes, then you need to add the SRV record to each email suffix DNS zone.

Note: to eliminate certificate and/or trust prompts, the Gateway certificate must match _discoverReceiver.email.suffix (e.g _discoverReceiver.corp.com). If you have multiple email suffixes, then you need the certificate to match every email suffix.

To enable email-based discovery, add a SRV record to each public email suffix DNS zone. Here are sample instructions for a Windows DNS server:

  1. In Server Manager, click Tools > DNS.
  2. In the left pane of DNS Manager, right-click your DNS domain, and click Other New Records.
  3. In the Resource Record Type dialog box, select Service Location (SRV), and then click Create Record.
  4. In the New Resource Record dialog box, do the following:
    1. In the Service box, enter the host value _citrixreceiver.
    2. In the Protocol box, enter the value _tcp.
    3. In the Port number box, enter 443.
    4. In the Host offering this service box, specify the fully qualified domain name (FQDN) for your NetScaler Gateway Virtual Server in the form servername.domain (e.g. gateway.company.com).
  5. Click OK to close the New Resource Record dialog box.
  6. Click Done to close the Resource Record Type dialog box.

Customize Logon Page

Logon Page Labels

When two factor authentication is configured on NetScaler Gateway, the user is prompted for User name, Password, and Password 2.

The Password field labels can be changed to something more descriptive, such as Active Directory or RSA:

To change the labels, edit a Portal Theme:

  1. Go to NetScaler Gateway > Portal Themes, and edit an existing theme. You can’t edit the built-in themes, so you’ll have to create one if you haven’t already.
  2. If you see the Login Page section on the left:
    • Click the pencil icon in the Login Page section.
  3. If you don’t see the Login Page section on the left:
    • On the right, in the Advanced Settings column, click Login Page to add it to the left.
  4. On the left, in the Login Page section, change the two Password fields to your desired text.
  5. Click OK to close the Login Page section.
  6. If you are using the RfWebUI theme, the default text size for the form field labels is 17px. However, the Portal Themes editor defaults to 12px. You can change it back to 16px or 18px by doing the following:
    1. In the Look and Feel section, click the pencil icon.
    2. Scroll down to the Common Attributes section.
    3. Change the Form Font Size drop-down to 16px or 18px.
    4. Click OK to close the Look and Feel section.
  7. In the Portal Theme section at the top of the page, you can Click to Bind and View Configured Theme to Preview your changes.
  8. You might have to invalidate the loginstaticobjects Integrated Caching Content Group (Optimization > Integrated Caching > Content Groups) before the changes appear. This seems to be true even if Integrated Caching is disabled.

 Logon Security Message (Disclaimer, EULA)

You can force users to agree to a EULA before they are allowed to login.

Clicking the Terms & Conditions link allows the user to view the EULA text that you have entered.

Do the following to configure the EULA:

  1. Go to NetScaler Gateway > Resources > EULA.
  2. On the right, click Add.
  3. Give the EULA a name, and enter some text. You can even enter HTML code. See the example posted by Chris Doran at Citrix Discussions.
  4. Scroll down, and click Create.
  5. Edit a Gateway Virtual Server.
  6. On the right, in the Advanced Settings column, click EULA.
  7. On the left, in the EULA section, click where it says No EULA.
  8. Click where it says Click to select.
  9. Click the radio button next to the previously created EULA, and click Select.
  10. Click Bind.
  11. Mike Roselli at Automatic EULA Acceptance by Cookie Rewrite Guide at Citrix Discussions details Rewrite policies that change the behavior so that users only have to accept the EULA once. It records acceptance in a cookie.
  12. Sam Jacobs Adding an EULA for AAA Login at CUGC explains how to enable the EULA on the AAA logon page.

Theme File Customization

The original themes (Default, Green Bubble, and X1) use files from /netscaler/ns_gui/vpn/js and /var/netscaler/logon/themes. A commonly edited file is /netscaler/ns_gui/vpn/js/gateway_login_form_view.js since this file is responsible for rendering the logon form.

The new RfWebUI theme is different than the original themes, because it pulls files from /var/netscaler/logon/LogonPoint/receiver. This means the customizations for NetScaler 11.0 won’t work with the new RfWebUI theme. When reviewing customization guides for NetScaler 11, be aware that most of them won’t work for the RfWebUI theme.

Citrix CTX202444 How to Customize NetScaler Gateway 11 logon Page with Links shows how to add links to the NetScaler Gateway 11 logon page. This only works in the Default, Green Bubble, and X1 themes (no RfWebUI theme).

Other Customizations

CTP Sam Jacobs at Adding Text, Links and Other Elements to the NetScaler Logon Page – Part 2 at CUGC explains how to add text to the RfWebUI theme logon page. The process for RfWebUI is quite different than the older themes:

  • Text is stored in /var/netscaler/logon/themes/<theme>/strings.<language code>.json
  • Custom CSS is stored in /var/netscaler/logon/themes/<theme>/css/theme.css
  • Sample Logon Page:
    Logon screen with footer.jpg

CTP Sam Jacobs at Adding Text, Links and Other Elements to the NetScaler Logon Page – Part 1 at CUGC explains how to modify custom.css and en.xml to add text below the logon box on the Logon Page. No Rewrite policies or source code modifications needed.

Citrix CTX215817 NetScaler : How to Customize Footer of NetScaler Gateway Login Page. This article does not work with the RfWebUI theme, but it works with the X1 theme.

Mike Roselli at Netscaler 11 Theme Customization – How to Add Links and Verbiage at Citrix Discussions has sample rewrite policies to customize the NetScaler Gateway logon page with additional HTML.

 

Craig Tolley Customising the NetScaler 11 User Interface – Adding Extra Content: add new sections to login page. These sections pull content from local HTML files.

 

Daniel Ruiz Set up a maintenance page on NetScaler Gateway: configure a Responder policy (see the blog post for sample HTML code). During maintenance, manually bind the Responder policy to the Gateway. Manually remove the policy after maintenance is complete.

 UDP Audio Through Gateway

From John Crawford at Citrix Discussions and Marius Sandbu Enabling Citrix Receiver audio over Netscaler Gateway with DTLS

Note: Enabling DTLS on the Gateway also enables the Gateway to support EDT (Adaptive Transport) and Framehawk.

Requirements for UDP Audio:

  • Citrix Receiver 4.2 or newer
  • UDP 443 allowed to NetScaler Gateway Virtual Server
  • UDP 16500-16509 allowed from NetScaler SNIP to the VDAs

To enable UDP Audio through Gateway, make changes on both the NetScaler Gateway Virtual Server, and in Receiver:

  1. Edit a NetScaler Gateway Virtual Server.
  2. In the Basic Settings section, click the pencil icon.
  3. Click More.
  4. Enable the DTLS option, and click OK.
  5. After enabling DTLS, it probably won’t work until you unbind the Gateway certificate, and rebind it.
    1. On the left, click where it says 1 Server Certificate.
    2. Click Add Binding.
    3. Click where it says Click to select.
    4. Click the radio button next to the same certificate that’s already bound. Click Select.
    5. Click Bind.
    6. Click Close.
    7. Click Continue to close the Certificate section.

Client-side configuration

There are two methods of enabling RTP on the client side:

  • Edit default.ica on the StoreFront server
  • Use GPO to modify the client-side config

To edit the default.ica file on the StoreFront server (h/t Vipin Borkar): Edit the file C:\inetpub\wwwroot\Citrix\Store\App_Data\default.ica and add the following lines to the Application section:

EnableRtpAudio=true
EnableUDPThroughGateway=true
AudioBandwidthLimit=1

To use GPO to modify the client-side config:

  1. Copy the receiver.admx (and .adml) policy template into PolicyDefinitions if you haven’t already.
  2. Edit a GPO that applies to Receiver machines. You can also edit the local GPO on a Receiver machine.
  3. Go to Computer Configuration | Policies | Administrative Templates | Citrix Components | Citrix Receiver | User Experience.
  4. On the right, edit the setting Client audio settings.
  5. Do the following in the Client audio settings dialog box.
    1. Enable the setting.
    2. Set audio quality as desired. Higher quality = higher bandwidth.
    3. Check to Enable Real-Time Transport.
    4. Check to Allow Real-Time Transport through Gateway.
  6. Click OK to close the Client audio settings dialog box.
  7. Look in the client-side registry at HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Citrix\ICA Client\Engine\Lockdown Profiles\All Regions\Lockdown\Virtual Channels\Audio to make sure the registry keys applied.
  8. When you launch the first session after enabling Real-Time Transport, you might be prompted to enable it through the client-side firewall.

To view the current UDP Audio sessions:

  1. In the NetScaler GUI, click the NetScaler Gateway node.
  2. On the right, click DTLS ICA Connections.
  3. This will show you all users that have UDP Audio connections through NetScaler Gateway. Note: this is different than EDT. To see EDT (UDP) HDX connections, click ICA Connections instead.

Citrix VPN from Mobile Devices

Links:

Citrix VPN Clients on Mobile Devices (Android, iOS) contain one of the following in their User-Agent strings. You can use this text in a Session Policy expression.

  • CitrixReceiver/NSGiOSplugin
  • CitrixReceiver/CitrixVPN

To block the Citrix VPN client connections from mobile devices, do one of the following:

  • Create an AppExpert > Responder > Policy with Action = DROP and Expression = HTTP.REQ.HEADER("User-Agent").CONTAINS("CitrixReceiver/NSGiOSplugin")|| HTTP.REQ.HEADER("User-Agent").CONTAINS("CitrixReceiver/CitrixVPN"). Either bind the Responder Policy Globally, or bind it to the Gateway vServers.
  • In your Gateway Session Policies, on the Client Experience tab, set the Plug-in Type to Java. If any of them are set to Windows/MAC OS X, then VPN for Mobile is allowed.

StoreFront – Rewrite X-Citrix-Via

When NetScaler Gateway communicates with StoreFront, it adds a header called X-Citrix-Via that contains the FQDN entered in the user’s address bar. StoreFront uses this header to find a matching Gateway object so StoreFront knows how to handle the authentication. In NetScaler 11.0 and newer, you can create a rewrite policy to change this header. This is useful when changing URLs or using DNS aliases for Gateways. See CTX202442 FAQ: Modify HTTP Header X-Citrix-Via on NetScaler for more details.

Here’s a sample rewrite policy for this header:

enable ns feature REWRITE

add rewrite action rwact_storefront replace "HTTP.REQ.HEADER(\"X-Citrix-Via\")" "\"mystorefront.mydomain.com\""

add rewrite policy rwpol_storefront "HTTP.REQ.HEADER(\"X-Citrix-Via\").NE(\"mystorefront.mydomain.com\")" rwact_storefront

bind vpn vserver mygateway-vs -policy rwpol_storefront -priority 100 -type REQUEST

Device Certificates  💡

NetScaler Gateway can require Device Certificates (machine based) before a user can login. The Endpoint Analysis Plug-in reads the machine certificate, and compares it to a CA certificate that is bound to the NetScaler Gateway Virtual Server.

  • Device Certificates are different from User Certificates.
  • Administrator permissions are required to access the machine certificate’s private key. NetScaler Gateway Plug-in (VPN client) can workaround this requirement.
  • OCSP is required. You can use Microsoft Online Responder.

To enable Device Certificates

  1. Create a OCSP Responder on NetScaler, and bind it to the CA Certificate. See CTX200290 How to Configure Device Certificate on NetScaler Gateway for details. At Traffic Management > SSL > Certificates > OCSP Responder.

    1. The URL for Microsoft Online Responder is http://ocsp_server_FQDN:80/ocsp.
    2. Misja Geuskens at Netscaler Device certificate checks fails with W2K12R2 Online responder says don’t check the Nonce box.
  2. Import CA certificates for Root and Intermediate. At Traffic Management > SSL > Certificates > CA Certificates.
  3. Right-click each CA certificate, and click OCSP Bindings.

    1. Select the OCSP Responder you created earlier.
  4. Bind the CA certificates to the Gateway Virtual Server in the CA certificates section.

  5. Enable Device Certificates in the NetScaler Gateway Virtual Server > Basic Settings > More section. Move the same CA certificates to the right.

User Experience

Users will be prompted to install the Endpoint Analysis plugin.

Click Yes to run the scan. Note: if the user is not an administrator of the local machine, then you must also install the NetScaler Gateway Plug-in (VPN client) to handle the security restrictions.

If there are multiple certificates on the client machine, the user will be prompted to select one.

The chosen machine certificate is stored in %localappdata%\Citrix\AGEE\config.js. The user won’t be prompted for certificate selection again unless you delete this file.

This same folder contains nsepa.txt, which lets you troubleshoot device certificate checking. The most common issue is lack of permissions, which is handled by installing the NetScaler Gateway VPN Plug-in. The Gateway VPN Plug-in version must match the firmware version.