9.14 Joining a Node to the Cluster (Rejoining a Cluster)

The cluster join command allows you to add a node back to the cluster so that the node is again visible to other servers in the cluster.

While the node is not active in the cluster, any changes in storage objects are not updated automatically for the node. For example, the following storage object changes are automatically updated only for nodes that are currently active in the cluster:

  • Creating, deleting, or expanding a clustered NSS pool

  • Creating, deleting, or expanding a clustered LVM volume group

  • Adding or removing segments in an NSS software RAID (that is used by a clustered NSS pool)

  • Creating, mirroring, or re-creating an SBD partition

  • Creating or deleting shared partitions

If OES Cluster Services is configured to autostart when a server is restarted, a node that has left the cluster automatically rejoins the cluster on reboot. A server restart automatically rescans devices, rescans storage objects, and remaps multipath devices. Thus, if you reboot a node that has left the cluster, a node automatically recognizes any storage object changes made while the node was not active in the cluster.

To rejoin a cluster without rebooting the server:

  1. Log in as the root user on the server that you want to join the cluster, then enter the following at a command prompt:

    cluster join
  2. (Storage object changes) If you modified shared storage objects while the node was not active in the cluster, you must rescan the storage objects in order for the node to recognize these changes:

    1. Log in to the node as the root user and open a terminal console.

    2. Scan for storage object changes. At the command prompt, enter

      nlvm rescan