OpenVMS Cluster Systems - OpenVMS Systems - HP

Cluster Storage Devices
6.5 Managing Cluster Disks With the Mount Utility
use MOUNT/CLUSTER and MOUNT/SYSTEM as described in the preceding
table.
Note: Only system or group disks can be mounted across the cluster or on a
subset of the cluster members. If you specify MOUNT/CLUSTER without the
/SYSTEM or /GROUP qualifier, /SYSTEM is assumed. Also note that each cluster
disk mounted with the /SYSTEM or /GROUP qualifier must have a unique
volume label.
6.5.2 Examples of Mounting Shared Disks
Suppose you want all the computers in a three-member cluster to share a disk
named COMPANYDOCS. To share the disk, one of the three computers can
mount COMPANYDOCS using the MOUNT/CLUSTER command, as follows:
$ MOUNT/CLUSTER/NOASSIST $1$DUA4: COMPANYDOCS
If you want just two of the three computers to share the disk, those two
computers must both mount the disk with the same MOUNT command, as
follows:
$ MOUNT/SYSTEM/NOASSIST $1$DUA4: COMPANYDOCS
To mount the disk at startup time, include the MOUNT command either in a
common command procedure that is invoked at startup time or in the computerspecific
startup command file.
Note: The /NOASSIST qualifier is used in command procedures that are designed
to make several attempts to mount disks. The disks may be temporarily offline or
otherwise not available for mounting. If, after several attempts, the disk cannot
be mounted, the procedure continues. The /ASSIST qualifier, which is the default,
causes a command procedure to stop and query the operator if a disk cannot be
mounted immediately.
6.5.3 Mounting Cluster Disks With Command Procedures
To configure cluster disks, you can create command procedures to mount them.
You may want to include commands that mount cluster disks in a separate
command procedure file that is invoked by a site-specific SYSTARTUP procedure.
Depending on your cluster environment, you can set up your command procedure
in either of the following ways:
• As a separate file specific to each computer in the cluster by making copies of
the common procedure and storing them as separate files
• As a common computer-independent file on a shared disk
With either method, each computer can invoke the common procedure from the
site-specific SYSTARTUP procedure.
Example: The MSCPMOUNT.COM file in the SYS$EXAMPLES directory on
your system is a sample command procedure that contains commands typically
used to mount cluster disks. The example includes comments explaining each
phase of the procedure.
Cluster Storage Devices 6–25