IBM Storwize V5000, Quick Installation Manual

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v When both ends of a SAS cable are inserted correctly, the green link LEDs next
to the connected SAS ports are lit.
Guidelines
Be aware of the following guidelines when you attach the cables to the SAS ports.
v No more than ten expansion enclosures can be chained to port 3 of a node
canister. The expansion enclosures in this chain should be installed below the
control enclosure (as shown in Figure 16 on page 21).
v No more than nine expansion enclosures can be chained to port 4 of a node
canister. The expansion enclosures in this chain should be installed above the
control enclosure (as shown in Figure 16 on page 21).
v No cable can be connected between a port on a left canister and a port on a
right canister.
v A cable must not be connected between ports in the same enclosure.
v Port 3 and port 4 of a control enclosure must not be cabled to the same
expansion enclosure.
v Port 3 or port 4 of a control enclosure must not be cabled to another control
enclosure.
v A connected port on the node canister must connect to a single port on an
expansion canister. Cables that split the connector out into separate physical
connections are not supported.
v Attach cables serially between enclosures. Do not skip an enclosure.
v
Each expansion enclosure is connected into the system by two SAS cables. Three
different lengths of SAS cable are available for this purpose. Lengths longer than
0.6 m are typically required to connect enclosures that are not adjacent.
– 0.6 m (feature code ACTA)
– 1.5 m (feature code ACTB)
– 3.0 m (feature code ACTC)
v The last enclosure in a chain must not have cables in port 2 of canister 1 and
port 2 of canister 2.
v Ensure that cables are installed in an orderly way to reduce the risk of cable
damage when replaceable units are removed or inserted.
v Arrange your cables to provide access to:
v3500179
Figure 15. SAS cable connectors
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Storwize V5000: Quick Installation Guide