D-Link DSN-5410-10 - xStack Storage Area Network Array Hard Drive Software Manual page 94

Dual controller systems provide redundancy for High Availability. Under normal conditions,
both controllers in the Primary Array function as a "Bound" pair. They operate together
and all system activity on the primary controller is mirrored to the redundant controller. In
the event of a controller failure, the system will automatically transfer all system
configuration information (including Management Port and Data Port IP addresses) and any
cached data to the redundant controller, without any interruption to the host servers.
When a primary controller failure occurs, the redundant controller becomes a "Survivor",
and the failed controller is held in a non-functional state. After repairing or replacing the
failed controller, the system must be shutdown and restarted to allow both controllers to
re-bind.
If the controllers are unable to bind during the system startup process, the system state will
appear as "Unable to Bind", and the reason for the failure will appear in the Main Display.
At a minimum, both controllers must be equipped with the same number of iSCSI data ports
and the same amount of Buffer Memory, and must be running the same version of software.
Figure 6-3. System Administration View – Controller Selected (Dual Controller Systems)
Refer to Section 6.2 for a description of the Details Tabs. The System Administration View
only displays a System Actions panel, which includes a "Force System Failover" selection
for testing the automated controller failover.
102 Chapter 6 System Administration