Use the XDELPAIR command to specify that XRC delete volume pairs
from an XRC session. When the XDELPAIR command processes, XRC stops
processing either a primary volume and its associated secondary volume,
or a utility volume. You can delete up to 100 volume pairs by listing
the 100 primary volume serial numbers in a single XDELPAIR command.
For each volume, the XDELPAIR command returns a timestamp indicating
that the data on the secondary volume is consistent with the data
that was on the primary volume at the specified time.
If you issue an XDELPAIR command for one or more volume pairs in
a session, the command operates the same in either a coupled or non-coupled
environment. Deleting the last volume in a coupled session will cause
the session to be uncoupled from the master data set.
If you issue an XDELPAIR command to delete a volume in
an enhanced session, the volume is removed from the primary and all
auxiliary sessions.
If you issue an XDELPAIR command to delete a volume
that is an XRCUTL utility device in an enhanced session, and the parmlib
value for number of sessions is not specified, then delete the utility
device to decrease the number of auxiliary sessions. To reduce the
potential impact of the decrease, suspend all volumes in the enhanced
session. If the volumes are suspended, the following additional processing
occurs:
- All volumes are withdrawn from one of the auxiliary sessions.
- The auxiliary session is drained of all remaining updates in cache.
- The auxiliary session is terminated.
- The specified XRCUTL device is removed from all remaining primary
and auxiliary sessions.
- Remaining utility devices are reassigned within the remaining
enhanced session members.
If you issue an XDELPAIR command to delete a utility
volume in an enhanced session, but the operation reduces the number
of volumes available to read below the NumberReaderTasks value ,
the XDELPAIR command is rejected.
Note: - XRC does not process any volumes in a list if there is a command
syntax error, or if any of the volumes in the list are not part of
the XRC session.
- You can delete XRC volume pair with the XDELPAIR command, regardless
of the status of the pair. Volume pairs in pending, duplex, copy,
seqcheck, and suspend status all become inactive when deleted, and
are no longer eligible for recovery.
- An XRC session remains active even when you have deleted all of
its pairs. Issue an XEND command to end the session or an XSUSPEND
command to suspend the session.
- Large batches of XDELPAIR commands issued to Duplex volumes may
result in significantly increased session delays. To avoid these delays,
consider issuing the XDELPAIR commands while all volumes are suspended,
or issuing them in small batches across a period of several minutes.
- To delete a volume pair that was added in the
same request with a utility pair using the LOGPLUS parameter, specify
only the primary volume. The utility volume pair is deleted automatically
and should not be specified in the XDELPAIR command.
For additional information about deleting utility volumes, refer
to Using XRC utility devices.