Building Disaster Recovery Serviceguard Solutions Using Metrocluster with Continuous Access XP P9000 for Linux B.12.00.00

In these situations, the remote array RAID manager instance allows the Metrocluster package to
determine the device group status and start successfully. The remote array RAID Manager requires
access to a command device configured on the remote array. Access to this command device at
the remote array can be configured using one of the following methods:
Using the XP or P9000 external storage feature (Remote Command Device)
A Remote Command Device (RCMD) is a device to which a command device in a remote XP array
is mapped. The RCMD is configured using the XP or P9000 external storage feature, through
inter-site replication links. On XP or P9000 array in a Metrocluster site, a command device from
the XP or P9000 array at the remote site is mapped to the local device using the XP or P9000
external storage feature. The mapped command device is then presented to the nodes in the site
to be used as a remote command device. This RCMD configuration is done between arrays on
both sites in a mutual fashion. For more information about the behavior of the command device
of a remote XP or P9000 array, see HP StorageWorks P9000 External Storage for Open and
Mainframe Systems User Guide available at http://www.hp.com/support/manuals -> storage
-> Storage Software -> Storage Device Management Software -> HP P9000 External Storage
Software or HP StorageWorks XP External Storage user guide available at http://www.hp.com/
support/manuals -> storage -> Storage Software -> Storage Device Management Software -> HP
XP External Storage Software.
Using extended SAN
The dedicated command device from the XP or P9000 array in the remote site is directly presented
to the nodes in the local site over an extended SAN. This configuration does not use the XP external
storage feature.
HP recommends configuring a remote array RAID Manager instance in all Metrocluster
configurations, especially in a 2-node configuration, as it is more robust. For more information
about configuring a remote array RAID Manager instance in Metrocluster, see “Configuring a
remote array RAID Manager instance” (page 30).
NOTE:
• Remote command device can be configured in Continentalclusters.
• Remote command device need not be configured when XP or P9000 Continuous Access
Journal replication is used.
Configuring a remote array RAID Manager instance
To configure the remote array RAID Manager instance in a Metrocluster environment with Continuous
Access XP or P9000:
1. Configure the command device to manage the remote XP or P9000 arrays. The XP array at
every site must have a command device exclusively for the nodes in the other site.
2. Configure the remote array RAID Manager instance on all the nodes in every site to manage
the remote XP or P9000 array. The RAID Manager instance that manages the local array is
referred as the local array RAID Manager.
3. Configure remote array RAID Manager instance in the /etc/mcxpca/raidmgr file for
automatic startup.
30 Metrocluster features