HP P6000 Cluster Extension Software Administrator Guide (5697-0986, June 2011)

NOTE:
Vdisks are virtual disks used in a HP P6000/EVA storage system for the storage of application data.
A DR group includes one or more vdisks in a P6000/EVA storage system. The DR group is the unit
in which P6000 Cluster Extension failover/failback operations are performed. For more information
about DR groups, see the HP P6000 Continuous Access Implementation Guide .
If the links between your storage systems are broken, depending on the configuration, the source
P6000/EVA array can log all the write I/Os of a DR group member to a write history log and replicate
the changes later after the links become available. In case of a failover, P6000 Cluster Extension takes
the appropriate action for each link/array status and makes sure that your application service has
the latest data.
Cluster setup considerations
For quorum considerations that apply to Windows and Linux, see:
• MSCS, page 11
• SLE HA cluster setup considerations, page 12
• RHCS cluster setup considerations, page 14
MSCS
MSCS depends on a quorum resource to maintain a persistent log of cluster configuration changes
and status, as well as a single point to resolve any possible events that could result in a split-brain
situation. P6000 Cluster Extension supports the following quorum configurations in which one site
failure will not cause the entire cluster to fail.
Windows Server 2008/2008 R2
• Node Majority
• Node and File Share Majority
Windows Server 2003
• Majority Node Set (MNS)
• Majority Node Set with File Share Witness
NOTE:
File Share Witness support:
• Windows Server 2003 supports only two node clusters when using File Share Witness.
• Windows Server 2003 Service Pack 2 supports MNS with File Share Witness.
• When using Microsoft Windows Server 2003 Service Pack 1 (SP1)-based server cluster or Windows
Server 2003 R2-based server cluster, you must apply a Microsoft patch to support MNS with File
Share Witness. See your Microsoft documentation for more information.
P6000 Cluster Extension has been certified to fulfill all requirements for geographically dispersed
Microsoft clusters. For certified configurations, see the Windows Vista Hardware Compatibility List
and the Windows Server Catalog on the Microsoft website.
HP P6000 Cluster Extension Software Administrator Guide 11