Technical data

Managing Storage Media
9.6 Setting Up Disk Volume Sets
PAYVOL1, which is listed first in the list of labels, becomes the root volume of
the set. The master file directory (MFD) for PAYVOL1 contains the directory
structure for the entire volume set.
2.
$ MOUNT DUA1:,DUA2:,DUA3: PAYVOL1,PAYVOL2,PAYVOL3
This example illustrates the use of one MOUNT command to mount a
previously created volume set.
9.6.3 Creating a Shadowed Disk Volume Set
The following example illustrates one way to create a shadowed volume set.
$ MOUNT/BIND=TEST3013 DSA3011/SHADOW=($1$DUA402:,$1$DUA403:),
DSA3012/SHADOW=($1$DUA404:,$1$DUA405:) TEST3011,TEST3012 TEST3013
This command creates a volume set with the logical name TEST3013. The volume
set TEST3013 is shadowed, and each element of the shadowset (TEST3011 and
TEST3012) is itself a volume set.
9.6.4 Creating a Disk Volume Set from an Existing Volume and a New Volume
To create a disk volume set from an existing volume and a new volume:
1. Use the DISMOUNT command to dismount the existing volume. Use the
/NOUNLOAD qualifier to logically dismount the volume from the drive. (The
volume, however, remains physically loaded on the drive.)
2. Use the INITIALIZE command to initialize the new volume, specifying the
device on which the volume is to be mounted and the volume label.
3. Use the MOUNT/BIND command to bind the new volume to the existing
volume, specifying the volume set name, the devices on which the volumes
are mounted, and the volume labels.
Specify the volume label of the existing volume first; it becomes the root
volume of the set. When you create a volume set from an existing volume,
you must specify the label of the existing volume first because the file system
must build on the existing directory structure.
Example
The following example shows how to create a disk volume set (called USERS)
from an existing volume. In this example, the volume USERFILES already
contains a directory structure and files; the volume is currently located on the
DUA1: device.
$ DISMOUNT/NOUNLOAD DUA1:
$ INITIALIZE DUA2: USERFILES2
$ MOUNT/BIND=USERS DUA1:, DUA2: USERFILES, USERFILES2
In the MOUNT/BIND command, you must specify the existing volume label
USERFILES before the volume label USERFILES2. USERFILES will be the root
volume of the set.
Caution
If you attempt to create a volume set from two or more volumes that
already contain files and data, the file system does not issue an error
message when you enter the MOUNT/BIND command. However, the
9–46 Managing Storage Media