A-16
DuraStor 412R/6320SS/7320SS Installation and User’s Guide
Active-Active Mode
In the active-active mode, the two RAID controllers cooperate to
provide redundancy. If one controller fails, the remaining
controller will take over the failed controller’s functionality. Each
controller has two fibre channel host ports, they are labeled in the
diagrams as FC1 and FC2.
In the active-active single-port mode, one FC host port is normally
active, and the other is normally passive. In a failed over condition,
the passive port of the surviving controller becomes active and
assumes the identity of the failed controller. This failover process
occurs without user intervention.
lists the presentation of
LUNs in active-active single-port mode.
In the active-active dual port mode, both FC host ports are active
and each controller normally presents the LUNs it owns on both of
its FC host ports. This provides the host with dual-ported access.
However, when a controller fails, the surviving controller presents
its LUNs on one of its FC host ports and the LUNs of the failed
controller on its other FC host port.
lists the presentation
of LUNs in active-active dual port mode.
Table A-5 Presentation of LUNs in Active-Active Single-Port Mode
Controller
Status
Controller 1
FC 1 Host Port
Controller 1
FC 2 Host Port
Controller 2
FC 1 Host Port
Controller 2
FC 2 Host Port
Both
controllers
online
Controller 1
LUNs
Passive
Controller 2
LUNs
Passive
Controller 1
fails
Inactive
Inactive
Controller 2
LUNs
Controller 1
LUNs
Controller 2
fails
Controller 1
LUNs
Controller 2
LUNs
Inactive
Inactive
DuraStor IUG - Online.book Page 16 Friday, July 19, 2002 3:06 PM
