User Manual

Storage System Description
34 Enterprise Virtual Array 3000 User Guide
Path A - Failover
Only
At initial presentation The units are brought online to
Controller A.
On dual boot or controller
resynch
If cache data for a LUN exists on a
particular controller, the unit will be
brought online there. Otherwise, the units
are brought online to Controller A.
On controller failover All LUNs are brought online to the
surviving controller.
On controller failback All LUNs remain on the surviving
controller. There is no failback except if a
host moves the LUN using SCSI commands.
Path B - Failover
Only
At initial presentation The units are brought online to
Controller B.
On dual boot or controller
resynch
If cache data for a LUN exists on a
particular controller, the unit will be
brought online there. Otherwise, the units
are brought online to Controller B.
On controller failover All LUNs are brought online to the
surviving controller.
On controller failback All LUNs remain on the surviving
controller. There is no failback except if a
host moves the LUN using SCSI commands.
Path A -
Failover/Failback
At initial presentation The units are brought online to
Controller A.
On dual boot or controller
resynch
If cache data for a LUN exists on a
particular controller, the unit will be
brought online there. Otherwise, the units
are brought online to Controller A.
On controller failover All LUNs are brought online to the
surviving controller.
On controller failback All LUNs remain on the surviving
controller. After controller restoration, the
units that are online to Controller B and set
to Path A are brought online to Controller
A. This is a one time occurrence. If the host
then moves the LUN using SCSI
commands, the LUN will remain where
moved.
Table 2: Failback Preference Settings (Continued)
Setting Point in Time Behavior