Configure Netscaler High Availability

This tutorial will provide you with instructions on how to configure Netscaler VPX in a high availability configuration. This will require you to have two netscaler appliances. For the purpose of this tutorial I will be using Citrix Netscaler VPX express edition virtual appliance and the appliance is available for download from the Citrix website. This tutorial assumes that you have two Netscaler appliances installed with a basic configuration.

Configure the Netscaler failover cluster with a Primary and Secondary node

The reason that we are going to statically assign the roles of primary and secondary is to make sure that during the initial configuration the primary node does not fail over to the additional node being added to the HA cluster. If we did not make this change the node that has the least uptime on the system clock would become the secondary node. So say for example we reboot the node that we want to be primary prior to introducing the additional node then the primary node would immediately failover to the additional node and this more than likely would not be a great scenario in a production environment.

So the first thing to do is establish a connection to both Netscaler appliances using a web browser. Notice on both of the Netscaler appliances that the Master state is Primary. Switch to the appliance that you plan to designate as the Primary>Expand System>Click on High Availability

Double click on the node to open up the HA properties>Select the radio button STAY PRIMARY>Click OK

You will notice that the node state has changed to STAY PRIMARY

Now switch to the node that you plan to designate as Secondary

Double click on the node to open up the HA properties>Select the radio button STAY SECONDARY>Click OK

You will notice that the node state has changed to STAY SECONDARY

Now move back to the web connection to your Primary node>Click the add button>Enter the IP address of your secondary node.

Pay particular attention to the second option “Turn off HA Monitor on interfaces/channels that are down” It is important that this option is selected because if monitoring is enabled on down interfaces then the appliance will failover because it assumes there is an issue with the appliances network interface.

If you switch over to the secondary Node you will notice that it has the Primary node and that het synchronization is in progress

Switch back to the Primary Nodes web interface. Now select the radio button Enabled (Actively participate in HA)>Click on OK

Switch back to the Secondary Node interface. Now select the radio button Enabled (Actively participate in HA)>Click on OK

You will now notice that both Nodes are in an up state and that the nodes designated as Primary and Secondary are still continuing to hold those roles and that the Synchronization state is In success and enabled

Verify that the network interfaces are being monitored for HA>Expand network>Interface

By default the active interfaces should have HA monitoring ON; however at the time of writing this article it appears that this is not the case. It is important to switch this option on so that the heartbeat is enabled for HA monitoring. This can be enabled by double clicking the interface and toggling the radio button to ON. This is only necessary for the Public interface (The interface where client connections are established from)

At the bottom of the screen there are some options to check statistics, force synchronization, and to force a failover. It is a good idea to test the failover to verify that it is functioning as expected