Veritas Volume Manager 5.0.1 Administrator's Guide, HP-UX 11i v3, First Edition, November 2009

Some failure scenarios do not result in a disk group failure policy being invoked,
but can potentially impact the cluster. For example, if the local disk detach policy
is in effect, and the new master node has a failed plex, this results in all nodes
detaching the plex because the new master is unaffected by the policy.
The detach policy does not change the requirement that a node joining a cluster
must have access to all the disks in all shared disk groups. Similarly, a node that
is removed from the cluster because of an I/O failure cannot rejoin the cluster
until this requirement is met.
Limitations of shared disk groups
Only raw device access may be performed via the cluster functionality of VxVM.
It does not support shared access to file systems in shared volumes unless the
appropriate software is installed and configured.
Note: The boot disk group (usually aliased as bootdg) cannot be made
cluster-shareable. It must be private.
The cluster functionality of VxVM does not support RAID-5 volumes, or task
monitoring for cluster-shareable disk groups. These features can, however, be
used in private disk groups that are attached to specific nodes of a cluster.
If you have RAID-5 volumes in a private disk group that you wish to make
shareable, you must first relayout the volumes as a supported volume type such
as stripe-mirror or mirror-stripe. Online relayout of shared volumes is
supported provided that it does not involve RAID-5 volumes.
If a shared disk group contains RAID-5 volumes, deport it and then reimport the
disk group as private on one of the cluster nodes. Reorganize the volumes into
layouts that are supported for shared disk groups, and then deport and reimport
the disk group as shared.
Cluster initialization and configuration
Before any nodes can join a new cluster for the first time, you must supply certain
configuration information during cluster monitor setup. This information is
normally stored in some form of cluster monitor configuration database. The
precise content and format of this information depends on the characteristics of
the cluster monitor. The information required by VxVM is as follows:
■ cluster ID
■ node IDs
463Administering cluster functionality
Cluster initialization and configuration