Cabling Connections Between Msa 2040 Controllers And Lff Drive Enclosures - HP MSA 2040 User Manual

Controller A
Controller B
Out
In
Out
In
Out
In
Out
In
Out
In
Out
In
In
In
Fault-tolerant cabling
Figure 1 1 Cabling connections between MSA 2040 controllers and LFF drive enclosures
The diagram at left (above) shows fault-tolerant cabling of a dual-controller enclosure cabled to MSA 2040
6 Gb 3.5" 12-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 (5B), 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 (above) shows the same storage components connected using straight-through
cabling. Using this method, if a drive enclosures fails, the enclosures that follow the failed enclosure in the
chain are no longer accessible until the failed enclosure is repaired or replaced.
1A
1B
2A
2B
3A
3B
4A
4B
5A
Out
5B
Out
1A Controller A
1B Controller B
2A
In
2B
In
3A
In
3B
In
4A
In
4B
In
5A
In
5B
In
Straight-through cabling
Connecting controller and drive enclosures
Out
Out
Out
Out
Out
Out
Out
Out
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