Perform the delta resync operation, 2 data center configuration – HP XP P9500 Storage User Manual
Page 140
Release a remote command device which is assigned to a mirror
Prerequisites
To release a remote command device which is assigned to a mirror, perform this operation per
mirror.
To release a remote command device which is assigned to a mirror
1.
Ensure that the Remote Web Console main window is in Modify mode. For detailed information
about how to do this, see HP P9000 Remote Web Console User Guide.
2.
Ensure that the Journal Operation window is open.
3.
In the tree, select a master journal or a restore journal from below Registered.
4.
From the mirrors, select and right-click the mirror that you want to release the assigned remote
command device.
5.
Select Mirror > Release R-Cmd Dev on the pop up menu.
6.
See the Preview list to check the settings that you have made.
7.
If you want to cancel a setting, select and right-click the setting and then click Delete.
8.
Click Apply to release the remote command device from the mirror. If an error occurs, right-click
the item on the Preview list, select Error Detail.
See the list in the Journal Operation window whether the remote command device is released
from the mirror or not. If the remote command device is not assigned, the column of the remote
command device is blank.
Perform the delta resync operation
The delta resync operation is performed during disaster recovery. This operation copies differential
data from the Continuous Access Synchronous S-VOL to the Continuous Access Journal S-VOL.
The delta resync operation is part of the Pair Resync operation. Follow instructions in
to execute delta resync.
2 data center configuration
In a 2DC configuration, update data is transferred from the Continuous Access Synchronous P-VOL
to the Continuous Access Journal master journal volume, and then to the Continuous Access Journal
S-VOL.
This is possible if the journal in the intermediate site was registered when 2DC Cascade was set to
Enable in the Edit Journal Volume dialog box. This option causes P-VOL data to be copied to the
Continuous Access Journal master journal (data is not copied to the Continuous Access Synchronous
S-VOL). Data in the master journal receives Continuous Access Journal sequence numbering for
write order and is pulled by the Continuous Access Journal secondary site to the S-VOL.
The Continuous Access Journal S-VOL contains the same data as the Continuous Access Synchronous
P-VOL. This allows business tasks to be taken over using the Continuous Access Journal S-VOL in
the event of primary site failure.
Though there are three sites, data is not stored in the intermediate data volume, only the journal
volume. Thus it is called, “2 data center”, or 2DC.
Figure 24 2 data center (2DC)
140 Continuous Access Journal configurations with Continuous Access Synchronous