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

brw-rw---- 1 root disk 253, 17 Nov 18 12:42 mpath18p1
3. Run the multipath -ll command to view the multipath device names and SCSI ID for your
volume groups for Red Hat Enterprise Linux.
[root@ Node1 ~]# multipath -ll
mpath18 (350002ac0192e0f50) dm-9 3PARdata,VV
[size=5.0G][features=0][hwhandler=0][rw]
\_ round-robin 0 [prio=2][active]
\_ 1:0:0:8 sdh 8:112 [active][ready]
\_ 1:0:1:8 sdp 8:240 [active][ready]
In the above example mpath18 needs to be put in the multipath_rescan.sh file.
Timing considerations
HP 3PAR Cluster Extension Software gives priority to storage system operations over cluster software
operations. If HP 3PAR Cluster Extension is invoked during a Remote Copy volume group group
member resynchronization (merge), or is gathering information about the remote storage system,
it waits until the requested status information is reported. This ensures the priority of data integrity
over cluster software failover processes.
This behavior can lead to failed resources:
• When a Remote Copy volume group member resynchronization (merge) is in progress, the
software waits until the Remote Copy volume group is in a normal state if the ApplicationStartup
resource property is set to RESYNCWAIT or until the resyncwaittimeout value.
• In an SLE HA environment, if the ResyncWaitTimeout object value is higher than the resource
startup timeout value.
NOTE: Because the failover environment is dispersed over two or more data centers, the failover
time cannot be expected to be the same as that of a single data center with a single shared disk
device. Therefore, you must adjust the resource startup timeout value and the resyncwaittimeout
CLX property value based on failover tests you perform to verify the proper configuration setup.
In an SLE HA environment, the timeout values for the start operation can be adjusted. In an RHCS
environment, the timeout value for the resource depends on the standard script resource agent
(/usr/ share/cluster/script.sh) timeout values.
Timing considerations 59