Preferred Controller Ownership

The preferred controller ownership of a logical drive or array is the controller of an active-active pair that is designated to own these logical drives. The preferred controller owner is the controller that currently owns the logical drive or array.

If the preferred controller is being replaced or undergoing a firmware download, ownership of the logical drives is automatically shifted to the other controller, and that controller becomes the current owner of the logical drives. This is considered a routine ownership change and is reported with an informational entry in the event log.

There can also be a forced failover from the preferred controller to the other controller because of I/O path errors. This is reported with a critical entry in the event log, and will be reported by the Enterprise Management software to e-mail and SNMP alert destinations.

The preferred owner for a logical drive is initially selected by the controller when the logical drive is created. Use the Array >> Change >> Ownership/Preferred Path pull-down menu option to change the preferred controller ownership for a selected array. To change the preferred controller ownership for a logical drive, use the Logical Drive >> Change >> Ownership/Preferred Path pull-down menu option.

Important: A Secondary Logical Drive in a Remote Mirror does not have a preferred owner. Instead, the ownership of the Secondary Logical Drive is determined by the controller owner of the associated Primary Logical Drive . For example, if Controller A owns the Primary Logical Drive in the primary storage subsystem, then Controller A owns the associated Secondary Logical Drive in the secondary storage subsystem. Controller ownership changes of the Primary Logical Drive cause a corresponding controller ownership change of the Secondary Logical Drive.

To shift logical drives away from their current owners and back to their preferred owners, use the Storage Subsystem >> Redistribute Logical Drives option.