Using stop and start replication to upgrade AFM and AFM DR

You can use replication stop and start method to assist an upgrade. Replication must be stopped on all filesets of a gateway node you want to upgrade.

When the replication is stopped, you can shut down the gateway node for an upgrade. Local data availability is not affected as the filesets can be accessed by other nodes. However, replication activity stops during upgrade. You must ensure that the replication is restarted after the gateway node is upgraded.

To restart replication, do the following steps:
  1. Plan downtime to upgrade IBM Storage Scale. AFM is stopped on the gateway node and the GPFS file system is unmounted and shutdown.
  2. Issue the following command to identify filesets that belong to the gateway node you want to upgrade:
    mmafmctl fsname getstate |grep GatewayNode
  3. Before upgrade, check if any messages are left in the queue. Wait until all pending messages are completed.
  4. Issue the following command to stop replication of the fileset:
    mmafmctl fsname stop -j filesetname
  5. Before you upgrade the gateway node, issue the following command to verify that the replication stopped:
    mmafmctl fsname getstate
  6. Unmount the file system and shut down GPFS on the gateway node.
  7. Upgrade the gateway node.
  8. Issue mmstartup to start the gateway node daemon.
  9. Check the node state by issuing mmgetstate.
  10. After the node is active, mount the file systems and issue the following command:
    mmafmctl fsname start -j filesetname
Recovery is initiated and replication starts.
Note: Synchronization of data between home and cache stops during the upgrade process. Recovery is run after you start replication to ensure that data at home and cache is synchronized.