Resynchronizing the snapshot to your database
When you have finished using a clone database or want to refresh it, you can resynchronize it with the original database. This is also known as refreshing the snapshot volume or merging the split snapshot image back to the current database image. After resynchronizing, the snapshot can be retaken for backup or decision-support purposes.
There are two choices when resynchronizing the data in a volume:
Resynchronizing the snapshot from the original volume.
Resynchronizing the original volume from the snapshot. This choice is known as reverse resynchronization. Reverse resynchronization may be necessary to restore a corrupted database and is usually much quicker than using alternative approaches such as full restoration from backup media.
The recovery method is different depending on how the SNAPSHOT_MODE is set in the snapplan.
See Snapshot mode.
Before resynchroninzing the snapshot to your database, make sure the following conditions are met:
Prerequisites
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Usage notes
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The db2ed_vmsnap command can only be executed on the primary host.
In a two-host configuration, the db2ed_vmsnap command imports the disk group that was deported from the secondary host and joins the disk group back to the original disk group. The snapshot volumes again become plexes of the original volumes. The snapshot is then resynchronized.
See the db2ed_vmsnap(1M) manual page for more information.
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Note: |
If you plan to resynchronize the snapshot image immediately after taking a snapshot, wait for approximately a minute or two after taking the snapshot and before running db2ed_vmsnap -o resync to allow time for Veritas Enterprise Administrator to refresh the objects. |
To resynchronize the snapshot image
In this example, the snapshot image is resynchronized with the primary database.
$ /opt/VRTS/bin/db2ed_vmsnap -D PROD -f snap1 -o resync
db2ed_vmsnap started at 2006-03-10 14:57:36
The option resync has been completed.
db2ed_vmsnap started at 2006-03-10 14:58:05
Now you can again start creating snapshots.