HP MSA 1040 User Guide (762783-001, March 2014)

Connecting controller and drive enclosures 23

Figure 11 Cabling connections between MSA 1040 controllers and SFF drive enclosures

The figure above provides sample diagrams reflecting cabling of MSA 1040 controller enclosures and

D2700 6 Gb drive enclosures.

The diagram at left shows fault-tolerant cabling of a dual-controller enclosure and D2700 6 Gb drive

enclosures featuring dual-expansion modules. Controller module 1A is connected to expansion module

2A, with a chain of connections cascading down (blue). Controller module 1B is connected to the lower

expansion module (4B) of the last drive enclosure, with connections moving in the opposite direction

(green). Fault-tolerant cabling allows any drive enclosure to fail—or be removed—while maintaining

access to other enclosures.

The diagram at right shows the same storage components connected using straight-through cabling. Using

this method, if a drive enclosure fails, the enclosures that follow the failed enclosure in the chain are no

longer accessible until the failed enclosure is repaired or replaced.

Both illustrations in Figure 11 show the maximum number of supported enclosures that can be cabled

together in an MSA 1040 system configuration: up to four enclosures (including the controller enclosure).

Controller A

Controller B

P2P1

Fault-tolerant cabling

Straight-through cabling

Controller A

Controller B

P2P1