HP XP P9500 Storage - Manual (Page 147)

D Continuous Access Journal configurations with External
Storage Access Manager
Continuous Access Journal and External Storage Access Manager can share the same data volume.
This section provides the planning information on sharing Continuous Access Journal configuration
with ESAM.
In this section, P-VOL indicates the primary volume, and S-VOL indicates the secondary volume.
These terms are used for both Continuous Access Journal and ESAM.
Overview
ESAM enables host-based applications to fail over between P9500 storage systems in the event
of an I/O failure to the primary storage system. Because of the way ESAM is configured, failover
is accomplished without restarting the application.
ESAM uses Continuous Access Synchronous to create a synchronous remote copy of a production
volume. While Continuous Access Synchronous is suited to large-scale disaster recovery, ESAM
is intended for recovery from on-sight disasters such as power supply failure.
Configurations with Continuous Access Journal secondary volumes
You can use the ESAM S-VOL as a Cnt Ac-J P-VOL. This configuration benefits the ESAM pair if
data in the P-VOL and S-VOL become inconsistent due to a disaster. In this case, you can recover
the data from the split Cnt Ac-J S-VOL.
For datails of disaster recovery, see HP P9000 External Storage Access Manager User Guide.
Figure 29 Sharing an ESAM S-VOL with Continuous Access Journal P-VOL
Overview 147