Prerequisite tasks, Adding the storage router to a cluster – HP StorageWorks IP Storage Router User Manual
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Configuring a High Availability Cluster
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IP Storage Router SR2122-2 User Guide
Prerequisite Tasks
Before performing any high availability cluster configuration tasks, make sure you
have configured system parameters, including the HA interface, as described in
Chapter 5, “Configuring the Storage Router”
Chapter 6, “Configuring System
When you configure SCSI routing instances to run in a high availability cluster,
follow these guidelines:
■
If you map targets using WWPN, be sure to specify both the primary WWPN
(the WWPN associated with the storage resource as known to the primary
storage router in the cluster) and the secondary WWPN (the WWPN
associated with the storage resource as known to the second storage router in
the cluster).
■
Automatic failover of a SCSI routing instance occurs if the Gigabit Ethernet
interface is unavailable or if all mapped targets are unavailable. If some
targets are available and others are not, the SCSI routing instance will not
automatically fail over. All SCSI routing instances will failover if the storage
router running the instances fails to exchange heartbeats within the high
availability cluster.
To maximize the potential for automatic failover in case of target
unavailability, map the targets associated with a single SCSI routing instance
to storage that is available through one Fibre Channel interface. Do not map
the targets associated with a single SCSI routing instance to storage that is
available through multiple FC interfaces.
This type of mapping minimizes the potential for a mixed target availability
condition, which prevents IP hosts from accessing some storage but does not
cause an automatic failover of the SCSI routing instance.
Adding the Storage Router to a Cluster
In most situations, you will completely configure a principal storage router
(including all cluster-wide settings), and then add a new, unconfigured storage
router or a minimally configured storage router to the cluster. A high availability
cluster is composed of two storage routers.