Adaptec 412R, Manual, Page: 132 / 210

B-2
DuraStor 412R/6320SS/7320SS Installation and User’s Guide
Active-Active Dual-Port Mode for SAN
At the heart of this strategy is the active-active dual-port operating
mode. In this mode, four fibre channel (FC) ports are
simultaneously active when both controllers are online. In the
event of a controller failure, two FC ports remain available to
service all host I/O.
Table B-1 illustrates how LUNs are presented
by each controller in this mode.
Note that when a controller fails, the surviving controller continues
to present its LUNs to its Host Port 0, and changes to present the
failed controller’s LUNs to its Host Port 1. The fibre channel node
and port world wide names corresponding to the failed controller’s
Host Port 0 (FC1) are also associated with its LUNs on the
surviving controller’s Host Port 1 (FC2).
Table B-1 LUN Presentation by Controller
Controller 1
Host Port 0
(FC1)
Controller 1
Host Port 1
(FC2)
Controller 2
Host Port 0
(FC1)
Controller 2
Host Port 1
(FC2)
Both
Controllers
Online Controller
1 LUNs
Controller
1 LUNs
Controller
2 LUNs
Controller
2 LUNs
Controller 1
Failed Inactive Inactive Controller
2 LUNs
Controller
1 LUNs
Controller 2
Failed Controller
1 LUNs
Controller
2 LUNs
Inactive Inactive
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