HP XP7 Storage - Manual (Page 13)

Figure 3 Journals
Data path
The physical transmission link between the primary and secondary systems is called the data path.
Continuous Access Journal Z commands and data are transmitted through the fibre-channel data
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 Z 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 40) .
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 16) and “Multiple journals per RAID Manager consistency group ” (page 35)
for more information.
Extended consistency groups
An extended consistency group (EXCTG) is a collection of journals in multiple local and remote
systems that allows you to guarantee data consistency during copy operations. With EXCTGs, you
perform operations on associated journals and their pairs at the same time. Journals can be
registered and removed from EXCTGs.
For complete information, see “Using extended consistency groups” (page 50) .
Remote Web Console
Remote Web Console provides a GUI and command line interface for accessing and managing
the storage system, including Continuous Access Journal Z.
Remote Web Console communicates with the SVP of each system over defined TCP/IP connections.
Business Continuity Manager
With Business Continuity Manager. you can perform the same Continuous Access Journal Z
operations as with the Remote Web Console GUI. In addition, you can automate pair operations
using scripts. Business Continuity Manager also provides system performance metrics thresholds,
which can help you avoid problems and optimize system performance.
Hardware and software components 13