HP Storage Mirroring V5.1 Software - Manual (Page 98)

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failure. However, if your source is an application server and an operation has been dropped, that one
file could cause the application not to start on the target in the event of a failure. In these cases,
manual snapshots of a bad state depend on the context of your environment.
If you are using the Management Console, check the Target Data State column to see the current
state of the data on the target. If you are using the scripting language, use the status target
DTCL command to determine the state of the data on the target.
Automatic snapshots
When Storage Mirroring transitions from a good state to a bad state, it will automatically attempt to
take a snapshot of the data before it leaves the good state and enters the bad state. For example, if
your data is in a good state and you start a mirror, before the mirror is started, Storage Mirroring will
automatically take a snapshot of the target. In the event the mirror fails to complete, you will have
a snapshot of the data on the target when it was in its last good state.
Only one automatic snapshot per connection is maintained on the target. When an automatic
snapshot is taken, it replaces any previous automatic snapshots.
NOTE: Because the driver for Volume Shadow Copy is started before the driver for Storage
Mirroring, if you revert any files on the source that are contained in your replication set,
Storage Mirroring will not be aware of the revert and, therefore, the file change will not
be replicated to the target. The file change will be mirrored to the target during the next
mirroring process.