A volume is not placed on the primary list if it does not meet
all of the criteria listed in
Table 1, or for one of the
following reasons:
- The volume is rejected. See Possible reasons for volume selection failure for more information.
- The VTOC index is broken or disabled, resulting in SMS not being
updated with space statistics from the Common VTOC Access Facility
(CVAF). This can also happen if OEM products bypass CVAF, the component
that notifies SMS of space changes. SMS not being updated with space
statistics can also result in a volume being overused.
- The volume was placed on the tertiary list because the number
of volumes in the storage group was less than the number of requested
volumes.
For example, this happens when a tape request of five volumes
causes a tape mount management buffer storage group containing only
two volumes to be marked tertiary, while an overflow storage group
or a quiesced storage group containing the requested five volumes
is marked secondary. The overflow volumes and quiesced volumes on
the secondary list are preferred over the tape mount management volumes
on the tertiary list. SMS will attempt to allocate space using the
overflow volumes first, then the quiesced volumes, and lastly the
tape mount management buffer volumes.
- The controller was IMLed while online to MVS. This can result
in the MVS device control blocks not reflecting the current state
of the volume. The device or devices should be varied offline and
back online to update the MVS control block status.
- RAID devices are eliminated from the primary list when STANDARD
is specified. Use NOPREF, the AVAILABILITY default, to allow both
SIMPLEX and RAID devices to be placed on the primary list.
For more information to help you determine why a particular volume
is selected or not selected, see Table 1.