ADC

Migrate a two-node cluster to an HA setup

March 27, 2026

Contributed by:

This document describes a guided procedure to migrate from a two-node cluster (nodes n0 and n1) to a two-node high availability (HA) setup. The procedure helps you preserve service continuity while you transition cluster-specific networking and configuration dependencies to an HA model.

Notes:

These steps are primarily for a two-node cluster (n0 and n1) to two-node HA migration.

The sequence of steps in this document is provided as guidance only. You might have to adjust it to fit your specific environment and requirements.

Before you begin

Validate your topology requirements.
Identify feature-specific impacts, such as CLAG, ECMP, and GSLB.

Procedure

Mark node n1 as passive.
- Optional: use the passive timeout feature to drain connections gracefully before making n1 passive. For more information, see Graceful shutdown of nodes.
Take a full backup.
- Back up ns.conf and ZebOS.
- From the cluster IP (CLIP) address, run the following command:
```
 add system backup
```
- For more information, see Backup and restore of cluster setup.
- Back up spotted configuration by using the following command:
```
 shell spottedconfig <nodeID>
```
  This command is supported in release 14.1 and later.
If CLAG is configured, make the necessary topology-specific adjustments.
- If only one interface is used between a node and the upstream switch, remove the LACP configuration from the upstream switch.
- If multiple links are used from a node (for example, n1) to the upstream switch, convert cluster-level LAG to node-level LAG on n1.
- Ensure that the LACP key (lacpKey) configured on the link aggregation (LA) channel is updated consistently on both nodes to match the upstream switch configuration.
If ECMP is used for traffic distribution, update the dynamic routing configuration to align with the target HA traffic flow.

For more information, see Using the Equal Cost Multiple Path (ECMP).
Remove cluster node n1 from the CLIP address.
Configure HA node n1 as secondary by setting the HA status as StaySecondary.
```
set ha node -hastatus STAYSECONDARY

add ha node 1 <NSIP_of_n0>
```
Apply the required configuration on node n1.
- Apply the required extracted configuration and restructured spotted configuration taken in step 2.
  
  Example: In a cluster setup, GSLB configuration such as site bindings might be associated with a node group. Identify and adapt such cluster-specific settings during migration.
- For spotted configuration details, see Striped, partially striped, and spotted configurations.
Take a backup on n0 (same as step 2).
Disable the cluster instance from the NSIP address of node n0.
On node n1, enable HA using the following command:
```
set ha node -hastatus ENABLE
```
Verify that the node n1 processes application traffic.
Remove the cluster instance on node n0 from NSIP.
Apply topology changes on node n0.
- Complete CLAG-related topology changes.
- Remove external traffic distribution mechanisms, if used (for example, ECMP), based on your topology plan.
Remove the backplane physically or disable backplane interfaces on both nodes.
- If necessary, convert the backplane to a HA SYNC VLAN. For more information, see Restricting high availability synchronization traffic to a VLAN.
On node n0, add n1 as the HA peer.
```
add ha node 1 <NSIP_of_n1>
```
If necessary, force HA synchronization on node n0. Then apply the backed-up spotted configuration and any remaining required configuration.

The official version of this product documentation is in English. Any non-English version is solely provided for your convenience and may include machine-translated content. For more information, please refer to the Machine Translation Disclaimer on Cloud Software Group home.

Was this helpful

NetScaler Secure Deployment Guide

Migrate a two-node cluster to an HA setup

March 27, 2026

Contributed by:

March 27, 2026

Contributed by:

Migrate a two-node cluster to an HA setup

Before you begin

Procedure

In this article