6.0 HP X9320 Network Storage System Administrator Guide (AW542-96009, December 2011)

Manual failover does not require the use of programmable power supplies. However, if you have
installed and identified power supplies for file serving nodes, you can power down a server before
manually failing it over. You can fail over a file serving node manually, even when automated
failover is turned on.
A file serving node can be failed over from the GUI or the CLI.
On the CLI, complete the following steps:
1. Run ibrix_server -f, specifying the node to be failed over in the HOSTNAME option. If
appropriate, include the -p option to power down the node before segments are migrated:
<installdirectory>/bin/ibrix_server -f [-p] -h HOSTNAME
2. Determine whether the failover was successful:
<installdirectory>/bin/ibrix_server -l
The contents of the STATE field indicate the status of the failover. If the field persistently shows
Down-InFailover or Up-InFailover, the failover did not complete; contact HP Support for assistance.
For information about the values that can appear in the STATE field, see “What happens during
a failover” (page 28).
Failing back a file serving node
After automated or manual failover of a file serving node, you must manually fail back the server,
which restores ownership of the failed-over segments and network interfaces to the server. Before
failing back the node, confirm that the primary server can see all of its storage resources and
networks. The segments owned by the primary server will not be accessible if the server cannot
see its storage.
To fail back a file serving node, use the following command. The HOSTNAME argument specifies
the name of the failed-over node.
<installdirectory>/bin/ibrix_server -f -U -h HOSTNAME
After failing back the node, determine whether the failback completed fully. If the failback is not
complete, contact HP Support for assistance.
NOTE: A failback might not succeed if the time period between the failover and the failback is
too short, and the primary server has not fully recovered. HP recommends ensuring that both servers
are up and running and then waiting 60 seconds before starting the failback. Use the
ibrix_server -l command to verify that the primary server is up and running. The status should
be Up-FailedOver before performing the failback.
Using network interface monitoring
With network interface monitoring, one file serving node monitors another file serving node over
a designated network interface. If the monitoring server loses contact with its destination server
over the interface, it notifies the management console. If the management console also cannot
contact the destination server over that interface, it fails over both the destination server and the
network interface to their standbys. Clients that were mounted on the failed-over server do not
experience any service interruption and are unaware that they are now mounting the file system
on a different server.
Unlike X9000 clients, NFS and CIFS clients cannot reroute file requests to a standby if the file
serving node where they are mounted should fail. To ensure continuous client access to files, HP
recommends that you put NFS/CIFS traffic on a user network interface (see “Preferring network
interfaces” (page 73)), and then implement network interface monitoring for it.
Comprehensive protection of NFS/CIFS traffic also involves setting up network interface monitoring
for the cluster interface. Although the management console will eventually detect interruption of a
file serving node’s connection to the cluster interface and initiate segment failover if automated
failover is turned on, failover will occur much faster if the interruption is detected via network
interface monitoring. (If automated failover is not turned on, you will begin to see file access
Cluster high availability 31