Journal volume areas – HP XP Continuous Access Software User Manual
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CAUTION:
You must register journal volumes in a journal group before creating a data volume pair in the
journal group for the first time.
You can add journal volumes under any of the following conditions:
• The journal group does not contain data volumes (that is, before creating a data volume pair
in the journal group for the first time, or after deleting all data volume pairs)
• All data volume pairs in the journal group are suspended
• Processing for changing a data volume pair's status (for example, deleting or suspending a
data volume pair) is not in progress
NOTE:
If a path from a host to a volume is defined, you cannot register the volume as a journal volume.
You can use Command View XP management stations or XP Remote Web Console to register
journal volumes.
If you add a journal volume when a remote copy operation is in progress (that is, when at least one
data volume pair exists for data copying), the journal volume's metadata area (see
) is unused, and only the journal data area is used. To make the metadata area usable, split
(suspend) all data volume pairs in the journal group, and restore (resynchronize) the pairs.
Adding journal volumes during a remote copy operation does not decrease the metadata usage rate
if the metadata usage rate is high.
Adding journal volumes during a remote copy operation might not change the journal data usage
rate until the journal volumes are used. To check the journal data usage rate, use the Usage Monitor
pane (see
Monitoring remote copy operations
).
•
Deleting journal volumes
You can delete journal volumes under any of the following conditions:
• The journal group does not contain data volumes (that is, before creating a data volume pair
in the journal group for the first time, or after deleting all data volume pairs)
• All data volume pairs in the journal group are suspended
You can use Command View XP management stations or XP Remote Web Console to delete journal
volumes.
•
Access from hosts to journal volumes
If a path from a host to a volume is defined, you cannot register the volume as a journal volume.
You cannot define paths from hosts to journal volumes. This means that hosts cannot read from
and write to journal volumes.
Journal volume areas
A journal volume consists of a metadata area and a journal data area. The ratio of the metadata area to
the journal data area is the same on all journal volumes within the journal group.
Metadata that manages the journal data is stored in the metadata area. For more information about the
metadata area, see
. Journal data that the metadata manages is stored in the journal data area.
Continuous Access XP Journal user guide
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