HP 3PAR Cluster Extension Software Administrator Guide (5697-1429, March 2012)

3. Restart the node that was shut down.
NOTE: The time to detect a storage outage due to failure of all paths to storage depends
on the setting for no_path_retry in the multipath software configuration. A value of fail
does not queue I/O in the event of a failure in all paths and returns an immediate failure. For
information about the recommended value for your environment, see the DM-Multipath
documentation.
Some resource agents, such as LVM, offer a mechanism called self_fence to take themselves
out of a cluster through node reboot when an underlying logical volume can no longer be
accessed. For supported options, see the RHCS documentation.
A storage replication link is down (RHCS)
If an HP 3PAR Cluster Extension configuration uses Remote Copy volume groups with failsafemode
enabled, the array disables access to the disk when it cannot replicate the I/O to the remote array.
In this situation, if a replication link is broken, the resource agents of configured resources, such
as lvm or fs, may be able to detect and take appropriate actions. The stop operation on a service
might fail due to the inability to stop individual resources cleanly because the disk is no longer
accessible for read/write operations. When the stop operation on a service fails, RHCS marks the
service as failed and the service does not automatically fail over to another node.
To recover from this situation, use the following procedure:
1. Remove the node that lost access to the storage by shutting down the node.
2. Follow the steps required to bring up a service in a failed state, as documented in the RHCS
administration guide. This process involves disabling the service, and then enabling it on the
node where the service is allowed to come online.
A data center is down (SLE HA and RHCS)
RHCS and SLE HA expect an acknowledgement from the fencing device before services are failed
over to another node. In the event of complete site failure, including fencing devices, clusters do
not automatically fail over services to surviving cluster nodes at the remote site. Manual intervention
is required in this situation. For instructions on bringing a service online, see the cluster software
documentation.
HP 3PAR Target arrays not configured with Remote Copy Links
Sometimes CLX Configuration Tool is not able to add an array even through the password file
exists and PATH variable is set properly for the HP 3PAR Inform CLI and you can execute HP 3PAR
Inform CLI command locally. The root cause for this problem is that the HP 3PAR Inform CLI command
showrcopy for this array does not show any target information (in case if target array is not
configured). So configure the 3PAR remote copy for the array first, then add the array to CLX
configuration through CLX configuration tool.
A storage replication link is down (RHCS) 83