Veritas Storage Foundation 5.1 SP1 Advanced Features Administrator"s Guide (5900-1503, April 2011)

The following types of point-in-time copy solution are considered in this document:
■ Primary host solutions where the copy is processed on the same system as the
active data.
See “Implementing point-in time copy solutions on a primary host” on page 126.
■ Off-host solutions where the copy is processed on a different system from the
active data. If implemented correctly, such solutions have almost no impact
on the performance of the primary production system.
See “Implementing off-host point-in-time copy solutions” on page 127.
Implementing point-in time copy solutions on a primary host
Figure 11-1 illustrates the steps that are needed to set up the processing solution
on the primary host.
Figure 11-1
Using snapshots and FastResync to implement point-in-time copy
solutions on a primary host
Volume
Primary host
If required, create a cache or empty
volume in the disk group, and use vxsnap
prepare to prepare volumes for snapshot
creation.
Cache or
empty
volume
Volume
Snapshot
volume
Apply the desired processing application
to the snapshot volumes.
Volume
Snapshot
volume
Use vxsnap make to create instant
snapshot volumes of one or more
volumes.
Volume
Snapshot
volume
If required, use vxsnap refresh to update the
snapshot volumes and make them ready for
more processing.
Repeat steps
3 and 4 as
required.
1. Prepare the volumes
2. Create instant snapshot volumes
3. Refresh the instant snapshots
4. Apply processing
Understanding point-in-time copy methods
About point-in-time copies
126