Technical data

Using BACKUP
11.11 Understanding Multivolume BACKUP Operations
a label, the first tape is labeled BACKUP, the second BACK02, and the third
BACK03.
• If you specified a single label on the command line using the /LABEL qualifier
and it matches the label of the first volume, BACKUP labels subsequent
volumes with the first four characters of the label from the first volume plus
the number of the volume in the sequence. For example, suppose you are
saving files that require three tapes and the first tape is labeled TAPE. The
second tape gets the label TAPE02, and the third tape gets the label TAPE03.
• If you specified multiple labels on the command line using the /LABEL
qualifier (without the /EXACT_ORDER qualifier), BACKUP uses the labels
you specify. If the operation requires more labels than you specified, BACKUP
uses the first four characters of the last volume label and the volume number
of the tape.
• You can use the /EXACT_ORDER qualifier in conjunction with the /LABEL
qualifier to specify the order in which you want BACKUP to use the labels.
BACKUP continues the operation as long as the label of the tape in the drive
matches the corresponding label on the command line. If you do not specify
enough labels on the command line to complete the operation, BACKUP
prompts you to enter a label for the tape in the drive.
As a safeguard against initializing or writing the wrong tape, BACKUP compares
the label that you specify on the command line to the label of the tape in the
drive. Section 11.12 describes how BACKUP processes tape labels and handles a
label mismatch.
11.11.2 MOUNT Messages When Backing Up Tapes
The MOUNT utility generates VOLINV messages on continuation tape volumes
during backups when you use devices that have loaders or when the stackers or
loaders become empty. The following example shows messages displayed:
%MOUNT-I-MOUNTED, ABCD03 mounted on _$4$MUA3: (HSC70)
%BACKUP-I-RESUME, resuming operation on volume 4
%MOUNT-F-VOLINV, volume is not software enabled
%BACKUP-I-READYWRITE, mount volume 4 on _$4$MUA3: for writing
Enter "YES" when ready: yes
%MOUNT-I-MOUNTED, ABCD04 mounted on _$4$MUA3: (HSC70)
Once the devices are put back on line or the media is made ready, the backup
session continues or finishes as expected. This problem will be addressed in a
future release.
11.12 Understanding BACKUP Tape Label Processing
After mounting a tape, BACKUP processes information stored in the volume
header record of the tape before writing to it. Specifically, BACKUP performs the
following actions:
• Checks the volume protection information to ensure that you have the right
to access the volume in the manner you requested.
• Checks the tape expiration date to prevent you from initializing a magnetic
tape that has not yet expired.
11–22 Using BACKUP