HP Storage Mirroring V5.1 Software - Manual (Page 97)

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To be completely assured that your data on the target is good, automatic and scheduled snapshots
only occur when the data is in a good Storage Mirroring state. However, manual snapshots can be
taken during any state. There are instances when you may want to take a manual snapshot, even if
the target data is in a bad state. For example, if you drop an operation, that does not necessarily
mean your data on the target is corrupt or the target would be unable to stand in for the source in
the event of a failure. A snapshot of a bad state may be useful and usable, depending on your
environment. If your source is a file server and an operation has been dropped, it is just one user file
that is out-of-date. All of the remaining target files are intact and can be accessed in the event of a
Target
Restarted
without
Connection
Persistance
Bad The target service has
been restarted and was
unable to persist
connection
information, therefore,
operations that were in
the queue have been
lost.
An automatic snapshot
will be taken after the
target restarts, if the
target data was in a
good state prior to the
target restart and the
connection is
configured to
auto-remirror on
auto-reconnect.
Scheduled snapshots
will be delayed until the
target data is back in a
good state.
Start a mirror, wait
until it is complete and
the data is in a good
state, and then take a
manual snapshot.
Restore
Required
Good
or
Bad
The data on the target
no longer matches the
data on the source
because of a failover.
This does not
necessarily mean that
the data on the target
is bad.
Scheduled and
automatic snapshots
will be delayed until a
restore is completed or
the Restore Required
state is overruled by a
mirror. Once the
restoration or mirror is
complete, automatic
and scheduled
snapshots will occur
normally.
Restore the target data
back to the source or
overrule the Restore
Required state by
performing a mirror.
Once the restoration or
mirror is complete,
manual snapshots can
be taken normally.
Snapshot
Reverted
Good
or
Bad
The data on the target
no longer matches the
data on the source
because a snapshot has
been applied on the
target. This does not
necessarily mean that
the data on the target
is bad.
Scheduled and
automatic snapshots
will be delayed until a
restore is completed or
the Snapshot Reverted
state is overruled by a
mirror. Once the
restoration or mirror is
complete, automatic
and scheduled
snapshots will occur
normally.
Restore the target data
back to the source or
overrule the Snapshot
Reverted state by
performing a mirror.
Once the restoration or
mirror is complete,
manual snapshots can
be taken normally.
Restore
Complete
Good Because the
restoration is complete,
the data on the source
and target is
synchronized.
Scheduled and
automatic snapshots
will occur normally.
Manual snapshots can
be taken normally.
Action State Description
Automatic Action
Taken for Scheduled
and Automatic
Snapshots
User Interaction
Required for Manual
Snapshots