5.5 HP StorageWorks X9720 Network Storage System Administrator Guide (AW549-96026, March 2011)

When automated failover is enabled, the management console listens for heartbeat messages that
the file serving nodes broadcast at one-minute intervals. The management console automatically
initiates failover when it fails to receive five consecutive heartbeats or, if HBA monitoring is enabled,
when a heartbeat message indicates that a monitored HBA or pair of HBAs has failed.
If network interface monitoring is enabled, automated failover occurs when the management console
receives a heartbeat message indicating that a monitored network might be down and then the console
cannot reach that interface.
If a file serving node fails over, you will need to manually fail back the node.
What happens during a failover
The following events occur during automated or manual failover of a file serving node to its standby:
1. The management console verifies that the standby is powered on and accessible.
2. The management console migrates ownership of the node’s segments to the standby and notifies
all file serving nodes and X9000 clients about the migration. This is a persistent change.
3. If network interface monitoring has been set up, the management console activates the standby
user network interface and transfers the IP address of the node’s user network interface to it.
To determine the progress of a failover, view the Status tab on the GUI or execute the ibrix_server
-l command. While the management console is migrating segment ownership, the operational status
of the node is Up-InFailover or Down-InFailover, depending on whether the node was powered up or
down when failover was initiated. When failover is complete, the operational status changes to
Up-FailedOver or Down-FailedOver. For more information about operational states, see “Monitoring
the status of file serving nodes” on page 57.
Both automated and manual failovers trigger an event that is reported on the GUI.
Setting up automated failover
The recommended minimum setup for automated failover protection is as follows:
1. Identify standbys for file serving nodes or specific segments. You must implement either server-
level or segment-level standby protection; you cannot implement both.
2. Identify power sources for file serving nodes. For APC power sources, associate file serving nodes
to power source slots.
3. Turn on automated failover.
If your cluster includes one or more user network interfaces carrying NFS/CIFS client traffic, HP
recommends that you identify standby network interfaces and set up network interface monitoring.
If your file serving nodes are connected to storage via HBAs, HP recommends that you set up HBA
monitoring.
Identifying standbys for file serving nodes
file serving nodes can be configured to provide standby service for one another in the following
configurations:
• 1 x 1. Set up standby pairs, where each server in a pair is the standby for the other.
• 1 x N. Assign the same standby to a certain number of primaries.
Contact HP Support for recommendations based on your environment.
The following restrictions apply to all types of standby configurations:
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