VERITAS Volume Manager 3.1 Administrator's Guide

Cluster Functionality
Cluster-related Volume Manager Utilities and Daemons
Chapter 7328
Note that the clusterid: field is set to cvm (the name of the cluster) and
the flags: field includes an entry for shared. When a node is not joined,
the flags: field contains the autoimport flag instead of imported.
vxdmpadm Utility
The vxdmpadm utility is a command line administrative interface for the
Dynamic Multipathing feature of VxVM. This utility can be used to list
DMP database information and perform other system administration
related tasks. For more information, see the manual page vxdmpadm(1M)
and “Disabling and Enabling Controllers”.
Enabling and Disabling Controllers
Volume Manager does not allow enabling or disabling of controllers
connected to a disk that is part of a shared VxVM disk group.
For example, consider a Galaxy disk array that is connected through
controller c0 to a host. This controller has a disk that is part of a shared
disk group. In such a situation, following operations fail on that host:
# vxdmpadm disable ctlr=c0
# vxdmpadm enable ctlr=c0
The following error message is displayed:
vxvm: vxdmpadm: ERROR:
operation not supported for shared disk arrays.
DMP Restore Daemon
The DMP restore daemon does not automatically failback I/Os for a disk
in an Active/Passive disk array if that disk is a part of a shared disk
group.
When a restore daemon revives a DISABLED primary path to a shared
disk in an Active/Passive disk array, DMP does not route the I/Os
automatically through the primary path, but continues routing them
through the secondary path. This behavior of the restore daemon is a
deviation from that on a single host environment.
A shared disk here means a disk which is a part of a shared disk
group.
In a clustered environment, failback of I/Os to the primary path happens
only when the secondary path becomes physically inaccessible tot he