Storage Mirroring Evaluation Guide

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1.2.4 Restoration
Restoration provides an easy method for copying replicated data from the target back to its
original location on the source. The process only requires you to select the source, target, and
the appropriate replication set. There is no need to select files or to remember where the data
came from on the source since that information is maintained by HP OpenView Storage
Mirroring.
Restoration can be used if the source data is lost due to a disk crash or when the most up-to-date
data exists on the target due to failover. At the time of a source machine failure, your HP
OpenView Storage Mirroring target will contain the same data as your HP OpenView Storage
Mirroring source. If you are using HP OpenView Storage Mirroring’s failover capabilities, users
can continue updating data on the target machine while the problems on the source are resolved.
Because of the continued updates on the target, when the source machine is ready to come back
online, the two machines will no longer contain the same data. Restoration is the process of
copying the up-to-date data from the target back to the original source or new source location
when bringing the source back online.
Like mirroring, restoration has a defined end point - when all of the selected files from the target
have been transmitted back to the source. When a restoration is complete, the source and target
are again synchronized.
Source Target
2/12/02
All files can be overwritten
Checksums can calculate which
blocks need to be restored
Files that are newer
on the target are restored
Identical files are not restored
Flexible restoration options allow you to choose
which files are restored from the target to the source.
11:14am
2/12/02
9:33am
during the restoration