HP Storage Mirroring V5.1 Software - Manual (Page 84)

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Verification
Verification is the process of confirming that the data on the target
is identical to the data on the source. Verification creates a log file
detailing what was verified as well as which files are not
synchronized. If the data is not the same, Storage Mirroring can
automatically initiate a remirror. The remirror ensures data integrity between the source and target.
Manual verification
A manual verification can be run anytime a mirror is not in progress.
1. Right-click the connection on the right pane of the Management Console and select Verify.
2. Select the verification options that you would like to perform.

Verify only — This option verifies the data and generates a verification log, but it does not
remirror any files that are different on the source and target.

Remirror files to the Target automatically—This option verifies the data, generates a
verification log, and remirrors to the target any files that are different on the source.

Only if Source file is newer than Target copy—If you are remirroring your files, you can
specify that only files that are newer on the source than the target be remirrored.

Use block checksum comparison/delta block transfer—Specify if you want the
verification process to use a block checksum comparison to determine which blocks are
different. If this option is enabled, only those blocks (not the entire files) that are different will
be identified in the log and/or remirrored to the target.
3. Click OK to start the verification.
NOTE: Because of the way the Windows Cache Manager handles memory, machines that are
doing minimal or light processing may have file operations that remain in the cache until
additional operations flush them out. This may make Storage Mirroring files on the target
appear as if they are not synchronized. When the Windows Cache Manager releases the
operations in the cache on the source, the files will be updated on the target.
NOTE: If you are using a database application, do not use the newer option unless you
know for certain you need it. With database applications, it is critical that all files,
not just some of them that might be newer, get mirrored.
NOTE: Database applications may update files without changing the date, time, or file
size. Therefore, if you are using database applications, you should use the block
checksum comparison to ensure proper verification and remirroring.