Adaptec 1966600 User Guide - Page 80

DuraStor 6220SS/7220SS Installation and User's Guide SAN Solution Strategies This section describes connecting the DuraStor storage subsystem active-active configuration to a Storage Area Network (SAN). Active-Active Dual-Port Mode 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 3-3 illustrates how LUNs are presented by each controller in this mode. Table 3-3. Controller LUNs Both Controllers Online Controller 1 Failed Controller 2 Failed Controller 1 Host Port 0 Controller 1 LUNs Inactive Controller 1 LUNs Controller 1 Host Port 1 Controller 1 LUNs Inactive Controller 2 LUNs Controller 2 Host Port 0 Controller 2 LUNs Controller 2 LUNs Inactive Controller 2 Host Port 1 Controller 2 LUNs Controller 1 LUNs Inactive 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 are also associated with its LUNs on the surviving controller's Host Port 1. 3-46