PowerScale OneFS 9.2.1.0 CLI Administration Guide

Fail over data to a secondary cluster

You can fail over to a secondary PowerScale cluster if, for example, your primary cluster becomes unavailable.

1. If your primary cluster is still online, complete the following steps:
   1. Stop all writes to the replication policy's path, including both local and client activity.
      This action ensures that new data is not written to the policy path as you prepare for failover to the secondary cluster.
   2. Modify the replication policy so that it is set to run only manually.
      This action prevents the policy on the primary cluster from automatically running a replication job. If the policy on the primary cluster runs a replication job while writes are allowed to the target directory, the job fails and the replication policy is deactivated. If this happens, modify the policy so that it is set to run only manually, resolve the policy, and complete the failback process. After you complete the failback process, you can modify the policy to run according to a schedule again.
      The following command ensures that the policy weeklySync runs only manually:

      isi sync policies modify weeklySync --schedule ""

2. On the secondary cluster, run the isi sync recovery allow-write command.
   The following command enables replicated directories and files specified in the weeklySync policy to be writable:

   isi sync recovery allow-write weeklySync

   NOTE SmartLock compliance mode WORM files, although replicated, are stored in a non-writable, non-erasable format.
3. Direct your users to the secondary cluster for data access and normal operations.