HP XP P9500 Storage - Manual (Page 9)

Data path
The physical links between the primary and secondary storage systems are referred to as the "data
path." These links include the Fibre Channel interface cables and switches. ESAM commands and
data are transmitted through the data path. The data path links the primary and secondary systems
through two types of Fibre Channel ports, Initiator and RCU Target ports.
Because paths are one-directional, and ESAM communicates in both directions, a minimum of two
data paths are needed; however, HP requires a minimum of two in each direction for greater
support and security of the data. A maximum of eight data paths in each direction are supported.
Therefore, the maximum number of logical paths between any two storage systems is sixteen (eight
forward and eight reverse).
Multipath software
Multipath software distributes the loads among the paths to the current production volume. For
ESAM, the multipath software duplicates the paths between the host and P-VOL, so that the paths
are in place between the host and the S-VOL also.
If a failure occurs in the data path to the primary system, or with the primary system, the multipath
software transfers host operations to the S-VOL in the secondary system.
Remote Web Console GUI
You perform ESAM operations using the Remote Web Console graphical user interface. Remote
Web Console is installed on a management computer. It communicates with the SVP of each
storage system over defined TCP/IP connections.
RAID Manager
Pair operations can be performed using RAID Manager. RAID Manager is installed on the host,
and commands are executed from a command device on the host. Disaster recovery operations
use a mix of Remote Web Console and RAID Manager.
Data replication
ESAM supports data sharing between the following volumes:
•
A volume in the primary P9500 system and a volume in secondary P9500 system.
•
Volumes in external storage systems.
•
A volume in the primary or secondary system and a volume in an external storage system.
Figure 2 Supported data sharing
Data replication 9