Fast copy techniques

If copies of all the page sets and logs are made while the queue manager is frozen, the copies will be a consistent set that can be used to restart the queue manager at an alternative site. They typically enable a much faster restart of the queue manager, as there is very little media recovery to be performed.

Use the SUSPEND QMGR LOG command to freeze the queue manager. This command flushes buffer pools to the page sets, takes a checkpoint, and stops any further log write activity. Once log write activity has been suspended, the queue manager is effectively frozen until you issue a RESUME QMGR LOG command. Whilst the queue manager is frozen, the page sets and logs can be copied.

By using copying tools such as FLASHCOPY or SNAPSHOT to rapidly copy the page sets and logs, the time during which the queue manager is frozen can be reduced to a minimum.

Within a queue-sharing group, however, the SUSPEND QMGR LOG command might not be such a good solution. To be effective, the copies of the logs must all contain the same point in time for recovery, which means that the SUSPEND QMGR LOG command must be issued on all queue managers within the queue-sharing group simultaneously, and therefore the entire queue-sharing group will be frozen for some time.