HP XP7 Storage - Manual (Page 12)

path and switches. The data path is connected to the primary and secondary systems through two
types of fibre-channel ports, Initiator and RCU Target ports. Continuous Access Journal requires
paths in both directions. More specifically, it requires paths with Initiator ports in the primary system
connected to RCU Target ports in the secondary system, and paths with Initiator Ports in the
secondary system connected to RCU Target ports in the primary system.
One data path connection is required. It is recommended that you use two or more independent
connections to provide hardware redundancy. A maximum of eight paths can be used.
For more information, see “Planning the data path” (page 33) .
Consistency groups and journals
Journals are used in Continuous Access Journal to guarantee data consistency across multiple pairs.
Consistency groups are used in other replication software for the same purpose. As a best practice,
you can assign RAID Manager consistency group numbers as journal IDs. See “journals” in
“System
requirements” (page 15) for more information.
Remote Web Console
Remote Web Console provides a GUI and command line interface for accessing and managing
the storage system, including Continuous Access Journal.
Remote Web Console communicates with the SVP of each system over defined TCP/IP connections.
RAID Manager (RAID Manager)
RAID Manager provides a command line interface for accessing and managing the storage system,
including Continuous Access Journal. You can perform the same Continuous Access Journal
operations with RAID Manager as you can with Remote Web Console. In addition, you can
automate pair operations using scripts.
If you want to use RAID Manager but it is not installed, contact your HP account team.
Reference Information
The following topics describe Cnt Ac-J copy operations and other features.
Overview of copy operations
initial and update copy operations including the underlying operations, such as journal processing
and differential data management.
Initial copy operation
The initial copy is executed when the primary system copies all the data in sequence from the
P-VOL directly to the S-VOL. Though journal volumes are not used during the initial copy, the copy
data in this operation is referred to as “base journal data”.
•
Creating or resynchronizing two or more pairs within the same journal results in the base
journal data being copied to the respective S-VOLs, one at a time. This extends the time
required for all the operations to be completed.
•
An initial copy operation can be performed to establish the pair — with no data copied
between the volumes. This can be done when data in the P-VOLs and S-VOLs are identical.
•
Continuous Access Journal pair data can also be copied using a Continuous Access
Synchronous initial copy operation. Doing this reduces the time to complete the copy operation.
See
“Planning pair volumes ” (page 23) for more information.
12 Continuous Access Journal overview