Specifications

11-25
Cisco SN 5428-2 Storage Router Software Configuration Guide
78-15471-01
Chapter 11 Maintaining and Managing the SN 5428-2 Storage Router
Controlling SCSI Routing Instances in a Cluster
Manual Failover
While failover of SCSI routing instances is automatic, there may be times when you wish to manually
move a SCSI routing instance from one storage router to another. The move may be temporary, after
which the instance will be moved back to its original location. At other times, you may want to move a
SCSI routing instance permanently to another storage router, ensuring that the instance will continue
running on the specified node whenever possible. The primary attribute allows you to specify a
“preferred” storage router for the specified SCSI routing instance.
As an example cluster scenario, a cluster is composed of two storage routers, Sys1 and Sys2. Sys1 is
currently running instances, scsi1 and scsi2, and is the primary storage router for both instances. Sys2 is
currently running instances, scsi3 and scsi4. The primary attribute for scsi3 and scsi4 is set to the default
setting of none, indicating no preferred storage router for failover for either instance. Both storage
routers have the same resources available for the configured SCSI routing instances and both storage
routers have failover by eligibility enabled (the default configuration).
Failover as Temporary Move
Referring to the example cluster scenario just described, the following procedure moves the SCSI
routing instances, scsi1 and scsi2, from their primary, or preferred, storage router, Sys1, to the other
storage router on a temporary basis. The first two commands in this procedure are issued from a CLI
session from Sys2; the remaining commands are issued from Sys1.
Once the failover is complete, return to your management session with Sys2 and verify—using CLI
commands described in Step 5 above—that the SCSI routing instances, scsi1 and scsi2, are now running
on that storage router.
This is considered a temporary move because Sys1 is still designated as the primary storage router for
the SCSI routing instances. If, for example, failover eligibility is manually re-enabled on Sys2 or if Sys2
is rebooted, scsi1 and scsi2 will stop running on Sys2 and will start up and run on Sys1.
Command Description
Step 1
enable Enter Administrator mode on Sys2.
Step 2
no failover eligibility on Disable failover by eligibility for Sys2.
Note This will prevent the SCSI routing instances from
automatically failing back over to Sys1 due to their
primary attribute setting.
Step 3
enable Enter Administrator mode on Sys1.
Step 4
failover scsirouter all Failover all SCSI routing instances running on Sys1.
Note Because there are only two storage routers in the cluster,
you do not need to specify the failover destination.
Step 5
show cluster
or
show scsirouter all brief
Verify that the SCSI routing instances are no longer running on the
storage router, Sys1.