HP OpenView Storage Mirroring User Guide (360226-002, May 2004)

7 - 2
File Differences Mirror Options
Block Checksum
All Server
Properties Source
Ta b
a
a.A checkmark enclosed in parentheses (!) indicates that the global option on the Server Properties Source tab can
be on or off. The use of this option does not change the action performed during the mirror.
File Differences
Mirroring
Option
Only if Source
is
Newer
Mirroring
Option
Block
Checksum
Mirroring
Option
Action Performed
(
!)
!
Any file that is different on the source
and target based on the date, time,
and/or size is transmitted to the target.
The mirror sends the entire file.
(
!)
!!
Any file that is newer on the source than
on the target based on date and/or time
is transmitted to the target. The mirror
sends the entire file.
!!
Any file that is different on the source
and target based on date, time, and/or
size is flagged as different. The mirror
then performs a checksum comparison
on the flagged files and only sends those
blocks that are different.
!! !
The mirror performs a checksum
comparison on all files and only sends
those blocks that are different.
(
!)
!!!
Any file that is newer on the source than
on the target based on date and/or time
is flagged as different. The mirror then
performs a checksum comparison on the
flagged files and only sends those blocks
that are different.
NOTE: The file differences options used with auto-remirror vary slightly. See Auto-Remirror on page 7-4 for details.
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 All option on the Server Properties Source tab to
ensure proper file comparisons.