HP StorageWorks Storage Mirroring Recover User's Guide (T5437-96008, November 2009)

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Pausing and resuming target processing
You can break the source/target connection without disconnecting the connection, so
that you can control the transmission of data across the network. You can do this by
pausing the target. If the target is paused, data is queued on the source until you
manually resume the target.
For example, you must pause the target while you perform a backup of database files
stored on the target because the database and log files must be backed up when they
are at the exact same point in time. For example, say the backup of the file
mydatabase.mdf begins on the target. While the backup program has access to the file,
Storage Mirroring Recover cannot write to the file. When the backup completes, Storage
Mirroring Recover writes to the file. Storage Mirroring Recover also writes to the
corresponding mydatabase.ldf file. When the backup gets to the mydatabase.ldf file, it no
longer matches the .mdf file. The database may require special startup procedures,
which may result in incomplete transactions being left in the database or data loss. To
workaround this scenario, pause the target before starting the backup and then resume
the target when the backup is complete.
While the target is paused, the Storage Mirroring Recover source cannot queue data
indefinitely. If the source queue is filled, Storage Mirroring Recover will automatically
disconnect the connections and attempt to reconnect them.
To pause a target, open the Replication Console and right-click a target server on the left
pane of the Replication Console. Select Pause Target. All active connections to that
target will complete the operations already in progress. You will see Pause Pending in
the Replication Console while these operations are completed. The status will update to
Paused after the operations are completed. Any new operations will be queued on the
source until the target is resumed. When you are ready to resume the target, right-click
the target and select Resume Target.
Note:
If you have multiple connections to the same target, all connections will be
paused and resumed.