HP XP P9500 Storage - Manual (Page 137)

If you specify the option of the delta resync operation, and the following conditions exist, errors
occur and the delta resync operation fails:
•
The secondary volume of the Continuous Access Journal pair for delta resync operation is
V-VOL.
•
The secondary volume of the Continuous Access Journal pair for delta resync operation is
assigned to the primary volume of Business Copy or the primary volume of Snapshot.
If the status of the Continuous Access Journal pair for delta resync operation does not change after
performing the delta resync operation, some of these requirements may not have been met. In this
case, ensure that the Continuous Access Synchronous pair, Continuous Access Journal pair, and
Continuous Access Journal pair for delta resync operation are in the required status.
Creating a delta resync pair
To create a Continuous Access Journal pair for delta resync pair
1. Install and setup Continuous Access Synchronous and Continuous Access Journal on the
required storage systems.
2. Create a Continuous Access Synchronous pair on the primary system, following the information
in the following sections:
•
“Prerequisite information for 3DC multitarget ” (page 133)
•
“Prerequisite information for creating the delta resync pair ” (page 135)
3. After the Continuous Access Synchronous pair status is PAIR, create the Continuous Access
Journal pair on the primary system, following the information in the following sections:
•
“Prerequisite information for 3DC multitarget ” (page 133)
•
“Prerequisite information for creating the delta resync pair ” (page 135)
4. Create a second Continuous Access Journal pair from the Continuous Access Synchronous
S-VOL to the Continuous Access Journal S-VOL. Specify the Initial Copy option as Delta.
Configuring the delta resync operation environment to support remote command
devices
This section explains how to configure the delta resync operation environment to support remote
command devices.
Establish immediate communications
When the delta resync operation has been performed and pair status is changed to PAIR, the delta
resync P-VOL must be updated from the host for longer than five minutes. This is required to insure
internal communications between the intermediate and remote sites.
However, you can work around this five-minute-plus update requirement by setting up command
devices and remote command devices. With remote command devices set up, communications
between the two sites is performed automatically, and the delta resync is ready to go when the
operation is executed.
This requires setting up two command devices and two remote command devices on each site —
the local, intermediate, and remote sites — as explained in the following general guidelines.
Consult the HP P9000 External Storage for Open and Mainframe Systems User Guide for more
complete information about remote command devices.
1.
Setup four command devices each on the local, intermediate, and remote sites.
2. Set up and dedicate two external ports and two target ports on each site for the
command/remote command devices. Configure paths between external ports and target ports.
For detail about the external ports, see HP P9000 External Storage for Open and Mainframe
Systems User Guide. For instruction on setting paths, see HP P9000 Provisioning for Open
Systems User Guide.
Delta resync configuration 137