Configuring high availability

To set up a high availability configuration, you create two nodes, each of which defines the other’s NetScaler IP (NSIP) address as a remote node. Begin by logging on to one of the two NetScaler appliances that you want to configure for high availability, and add a node. Specify the other appliance’s NetScaler IP (NSIP) address as the address of the new node. Then, log on to the other appliance and add a node that has the NSIP address of the first appliance. An algorithm determines which node becomes primary and which becomes secondary.

Note:

The GUI provides an option that avoids having to log on to the second appliance.

The following figure shows a simple HA setup, in which both nodes are in same subnet.

Figure 1. Two NetScaler Appliances Connected in a High Availability Configuration

localized image

Adding a remote node

To add a remote NetScaler appliance as a node in a high availability setup, you specify a unique node ID and the appliance’s NSIP. The maximum number of node IDs in an HA setup is 64. When you add an HA node, you must disable the HA monitor for each interface that is not connected or not being used for traffic. For CLI users, this is a separate procedure.

Note:

To ensure that each node in the high availability configuration has the same settings, you should synchronize your SSL certificates, startup scripts, and other configuration files with those on the primary node.

To add a node by using the command line interface

At the command prompt, type:

  • add ha node <id> <IPAddress>
  • show ha node

Example

> add ha node 10 203.0.113.32

To disable an HA monitor by using the command line interface

At the command prompt, type:

  • set interface <ifNum> [-haMonitor ( ON | OFF )]
  • show interface <ifNum>

Example

> set interface 1/3 -haMonitor OFF
 Done

To add a remote node by using the GUI

Navigate to System > High Availability and, on the Nodes tab, add a new remote node, or edit an existing node.

Disabling or Enabling a Node

You can disable or enable only a secondary node. When you disable a secondary node, it stops sending heartbeat messages to the primary node, and therefore the primary node can no longer check the status of the secondary. When you enable a node, the node takes part in the high availability configuration.

To disable or enable a node by using the command line interface

At the command prompt, type one of the following commands:

  • set ha node -hastatus DISABLED
  • set ha node -hastatus ENABLED

To disable or enable a node by using the GUI

  1. Navigate to System > High Availability and, on the Nodes tab, open the node.
  2. In the High Availability Status list, select ENABLED (Actively Participate in HA) or DISABLED (Do not participate in HA).

Removing a Node

If you remove a node, the nodes are no longer in high availability configuration.

To remove a node by using the command line interface

At the command prompt, type:

rm ha node <id>

Example

> rm ha node 10
  Done

To remove a node by using the GUI

Navigate to System > High Availability and, on the Nodes tab, delete the node.

Configuring high availability