HP EVA Cluster Extension Software Administrator Guide (5697-2445, July 2013)

Depending on the application and the resource property values, the resource tries to start on
different nodes several times. If the remote data center is down, this looks like the application
alternates (bounces) between the surviving systems. This happens until the application property
values are reached or until the user disables the restart of the resource.
This could be also the case if the ApplicationStartup resource property has been set to
FASTFAILBACK.
If a DR group state is discovered that does not allow bringing the application/package on any
system in the cluster, a cluster error is reported and the resource fails on all systems. This could
lead to the same behavior as described for an EVA Cluster Extension data center error.
In any case, HP does not recommend restarting a failed application/package without investigating
the problem. A failed Cluster Extension EVA resource indicates the need to check the status of the
DR group and its member vdisks and decide whether it is safe to continue or not.
All cluster nodes must to be able to communicate with the management server
All cluster nodes must be able to communicate with the management server that hosts the HP EVA
SMI-S server.
If there a communication error message during the initialization phase in the EVA Cluster Extension
log file, verify that the HP EVA SMI-S server can look up the cluster node names correctly and
connect to the cluster nodes. Use nslookup and ping to do this. You can also use the hosts file
to add cluster host names for name resolution to make sure that the HP EVA SMI-S server can
resolve names.
If there is a communication error message during the initialization phase in the EVA Cluster Extension
log file, use nslookup and ping to check if the node is able to look up the HP EVA SMI-S server
correctly and can connect to it. You can also use the hosts file to add cluster host names for name
resolution to ensure that the cluster node can resolve other system names.
This applies to all cluster nodes.
Failing physical disk resources during online attempt of the resource group
When resource groups that use EVA Cluster Extension for DR group failover are brought online,
physical disk resources fail for two reasons:
• The physical disk resource does not have a dependency on its Cluster Extension EVA
resources/packages configured. Review the setup steps for Cluster Extension EVA resources.
• The DR group is created with access mode disabled and has not been set to read-only access
for the destination vdisk(s). The disk resource fails initially. After rescanning the disks in the
Device Manager (disk management), the physical disk resource goes online as expected.
However, the physical disk resource might fail again after a later server reboot. Setting the
destination vdisk access mode to read-only solves this issue.
Physical disks cannot be added to cluster because physical disk number or drive
letter not shown in menu when creating physical disk resources
If you cannot see the drive letter or disk when trying to add a new resource:
• Restart the Failover Cluster Manager GUI cluadmin.msc.
• Ensure that the cluster group is online on the current host in which you are configuring the
disk. If having the cluster group online on the current host does not solve the problem, then
proceed with the solution described in the next bullet item.
• Fail back the DR group to the EVA array where you originally created the disk partition and
the drive letter.
Use the Failover Cluster Manager GUI on the node where you originally created the disk partition
and drive letter. Create the physical disk resource there.
Failover error handling 79