Handling Failed Control Modules

The member behavior when a control module is removed or fails depends on the number and type of control modules, the network cabling configuration, and the cache mode settings. See the Hardware Maintenance manual for your array model for detailed information about array-specific control module and network failover behavior.

In a dual control module array, if the secondary control module is removed or fails, the remaining control module may enter write-though mode depending on the cache mode policies.

In a dual control module array, if the active control module fails, the secondary control module automatically takes over and become active. If there is a network connection to the active control module, the control module failover will be transparent to applications; however, iSCSI initiators must reconnect to the group IP address.

If the only functioning control module fails, the member will be inaccessible from the network and you may experience data loss.

If a control module fails, replace it as soon as possible with the same control module type.

Caution: Do not mix control module types in an array.

For information about replacing a control module, see the Hardware Maintenance manual for your array model or contact your array support provider. Do not remove a failed control module until you have a replacement.