System information

Advanced Functions
5-19
The steps to set up the active-passive and active-active connections are almost the same. You simply need to specify all
the LUNs to the same preferred controller in the RAID GUI.
The Configuration Tasks table shown below details each configuration task according to the example given in Figure 5-
10.
Configuration Tasks
5.3.4 Controller and Path Failover/Failback Scenarios
By incorporating with the MPIO driver, the access to any virtual disk can be continued when one of the controller is failed.
Two principles should be cared for proper operation:
1. MPIO driver must be installed in the hosts.
2. All virtual disks must be mapped to the host across two controllers.
Path Failover Across Controllers
The paths to a VD on its preferred controller are called active paths, while the paths on the counterpart are called standby
paths. When all active paths are failed, the MPIO driver directs the traffic to standby paths. Figure 5-11 depicts the
scenario.
Tasks Instructions
Create Virtual volumes and specify the preferred
controller
RAID Management > Disk Groups > Create DG0 and DG1
RAID Management > Logical Disks > Create DG0LD0 >
Specify the preferred controller as ctla
RAID Management > Logical Disks > Create DG1LD0 >
Specify the preferred controller as ctla
Select Storage Provisioning method RAID Management > Storage Provisioning > Symmetric
Add WWPN of HBAs to hosts HBA0 WWPN -> Host 0 -> Host Group 0
HBA1 WWPN -> Host 1 -> Host Group 0
Map LUNs to host groups DG0LD0 and DG1LD0 -> Host Group 0
Note
The path failure may be caused by pure path failure or controller failure.
DG0LD0
DG1LD0
Host Group 0
DG0LD0
DG1LD0
Host Group 0
Host
Controller BController A
Host
Controller BController A
Figure 5-11 Controller failover scenario