The Rear Panel; Dual Controller Models - Infortrend EonStor DS 4000 Series Hardware Manual

The Rear Panel

Dual Controller Models

Dual controller systems are indicated by an "R" in their model number (please refer
to Model Naming
the second controller module will take over in a manner that is transparent to
application servers.
A
Conventions. In dual controller configuration, if one controller fails,
A
B
A
B
A
22
B
B