Pair Operations; Pair Operations Workflow; Check Pair Status; Create Pairs - HP StorageWorks P9000 User Manual

6 Pair operations

This chapter provides prerequisite information and instructions for performing Continuous Access
Synchronous operations.

Pair operations workflow

Basic Continuous Access Synchronous operations follow:
1. Check prerequisites for each procedure.
2. Always check pair status. Each Continuous Access Synchronous operation requires the pair
to be in a specific status.
3. Create the pair, in which the S-VOL becomes a duplicate of the P-VOL.
4. Split the pair, which separates the P-VOL and S-VOL and allows read/write access to the
S-VOL if desired.
5. Resynchronize the pair, in which the S-VOL again mirrors the ongoing, current data in the
P-VOL.
6. Release a pair.
For disaster recovery procedures, see

Check pair status

Every Continuous Access Synchronous operation requires that the pairs have a specific status.
Before performing any operation, check pair status.
Find status requirements under the Prerequisites topics for each operation.
To view a pair's current status in the GUI, or review status definitions, see
(page 52).

Create pairs

When you create the initial copy, all data in the P-VOL on the primary system is copied to the
S-VOL on the secondary system. The P-VOL remains available to the host for I/O operations.
Information on External Storage Access Manager pairs also displays on the Pair Operation window.
See the HP StorageWorks P9000 External Storage Access Manager User Guide for information.
Prerequisite information
The following information is provided to help you prepare for the Paircreate operation:
The initial copy is performed from the primary system.
S-VOLs must be offline to all hosts.
You will select the primary and secondary volumes to be paired by individual volume's port,
GID, and LUN CU and/or LDEV numbers. You should have this information on hand.
Ports must be configured for Continuous Access Synchronous. See
(page 37)
The primary and secondary systems must be configured for Continuous Access Synchronous.
See "Configure storage systems, define logical paths" (page 38)
Stop Performance Monitor before performing the initial copy to avoid overloading with TCP/IP
traffic.
If you are creating External Storage Access Manager pairs, have the HP StorageWorks P9000
External Storage Access Manager User Guide on hand for specific information.
P-VOL Fence Level settings
46 Pair operations
"Planning and procedures for disaster recovery" (page
for more information.
"Monitor pair status"
"Define port attributes"
for more information.
65).