Veritas Volume Manager 5.1 SP1 Administrator"s Guide (5900-1506, April 2011)

Until the disk group is upgraded, it may still be deported back to the release from
which it was imported.
To use the features in the upgraded release, you must explicitly upgrade the
existing disk groups. There is no "downgrade" facility. After you upgrade a disk
group, the disk group is incompatible with earlier releases of VxVM that do not
support the new version. For disk groups that are shared among multiple servers
for failover or for off-host processing, verify that the VxVM release on all potential
hosts that may use the disk group supports the disk group version to which you
are upgrading.
After upgrading to Storage Foundation 5.1SP1, you must upgrade any existing
disk groups that are organized by ISP. Without the version upgrade, configuration
query operations continue to work fine. However, configuration change operations
will not function correctly.
To list the version of a disk group, use this command:
# vxdg list dgname
You can also determine the disk group version by using the vxprint command
with the -l format option.
To upgrade a disk group to the highest version supported by the release of VxVM
that is currently running, use this command:
# vxdg upgrade dgname
About the configuration daemon in VxVM
The VxVM configuration daemon (vxconfigd) provides the interface between
VxVM commands and the kernel device drivers. vxconfigd handles configuration
change requests from VxVM utilities, communicates the change requests to the
VxVM kernel, and modifies configuration information stored on disk. vxconfigd
also initializes VxVM when the system is booted.
The vxdctl command is the command-line interface to the vxconfigd daemon.
You can use vxdctl to:
■ Control the operation of the vxconfigd daemon.
■ Change the system-wide definition of the default disk group.
In VxVM 4.0 and later releases, disk access records are no longer stored in the
/etc/vx/volboot file. Non-persistent disk access records are created by scanning
the disks at system startup. Persistent disk access records for simple and nopriv
disks are permanently stored in the /etc/vx/darecs file in the root file system.
265Creating and administering disk groups
About the configuration daemon in VxVM