12.17 Changing an Assigned Volume ID

Novell Cluster Services supports NCP client access to cluster-enabled NSS volumes by using a unique volume ID to mount the volume in the cluster. The volume ID is used by an NCP client only for automatic reconnects to the volume after failover or migration of a cluster resource.

Valid volume ID values are 0 to 254 (up to 255 mounted volumes per server). When you create a new volume on a cluster-enabled pool, Cluster Services automatically assigns it a volume ID that is unique in the entire cluster and writes the value to the cluster resource load script for the pool. Values start at 254 for the first volume in the cluster and decrease for each new volume. You can view the volume IDs assigned on a node by using the ncpcon volumes command.

In older operating systems, there was a mounted volume limit of 64 volumes (values 0 to 63). Some older applications might have hardcoded the old maximum limit of 64 mounted volumes, and might not be able to handle volume IDs greater than 63. You can use the Clusters plug-in to iManager to modify the volume ID in the scripts for a given cluster resource in order to specify a value that works for the application.

Changing the volume ID does not affect the ability to log in to, back up, or access the data. However, there is a brief disruption of service as the cluster resource is offlined and onlined to apply the script changes. If you modify the volume ID for a volume in the cluster resource scripts, ensure that you do the following: