Technical data

Managing Storage Media
9.8 Mounting Tape Volume Sets
2.
$ INITIALIZE MUA0: MAIN
$ MOUNT/OVERRIDE=IDENTIFICATION/INITIALIZE=CONTINUATION MUA0:,MUA1:
This example shows the use of the /INITIALIZE=CONTINUATION qualifier
for mounting volume sets. It also shows how the system creates volume
identifiers for continuation volumes.
The volume labeled MAIN is mounted on the MUA0: drive. The second
volume in the set receives the volume identifier MAIN02 and is mounted on
the MUA1: drive. The third volume in the set receives the volume identifier
MAIN03 and is mounted on the MUA0: drive.
To ensure that any volume added to the tape volume set is initialized prior to
being written to, mount the volume with the /INITIALIZE=CONTINUATION
qualifier. The default is /NOINITIALIZE.
3.
$ MOUNT MUA0:,MUA1: SUN
In this example, the first volume in the set is labeled SUN and is mounted
on the MUA0: drive. The second volume receives the identifier SUN_02 and
is mounted on the MUA1: drive. The third volume receives the identifier
SUN_03 and is mounted on the MUA0: drive.
4.
$ MOUNT MUA0:,MUA1: SUN,MOON
In this example, a continuation volume with two volume identifiers, SUN and
MOON, is mounted on MUA0: and MUA1:, respectively. If a third volume
is added to the set, it is given the identifier MOON03 and is mounted on the
MUA0: drive.
9.8.2.3 Disabling Automatic Switching
If your site prelabels volumes, you must disable automatic volume switching to
avoid overwriting these labels. To explicitly override automatic volume switching,
specify the /NOAUTOMATIC qualifier when mounting a tape volume. (The
default is /AUTOMATIC.) Note that if you allocate only one drive to the tape
volume set, automatic volume switching is implicitly disabled.
When a user is reading or writing to a magnetic tape and the tape reaches end-
of-tape position, the system suspends processing and sends a request to mount
the next tape in the volume set. For example:
%%%%%%%%%%% OPCOM, 28-MAY-2000 15:23:31.78 %%%%%%%%%%%
request 3, from user PLAW
MOUNT new relative volume 2 (DW0QT2) on MUA1:
The user does not see this message and might not realize that another tape is
needed to complete the read or write operation.
Example
$ MOUNT/NOAUTOMATIC MUA0: ABCD,EFGH
The command in this example tells MOUNT not to supply its own label for the
second volume but, instead, to use the ones specified in the MOUNT command.
9–54 Managing Storage Media