Cable requirements for expansion enclosures
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Cable requirements for expansion enclosures
When adding storage, use only Seagate or OEM-qualified cables, and observe the following guidelines:
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When installing SAS cables to expansion modules, use only supported HD mini-SAS (SFF-8644) x4 cables.
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Qualified HD mini-SAS cables, not to exceed 5 m (16.40’), are used to connect cascaded enclosures in the rack.
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The maximum expansion cable length allowed in any configuration is 5 m (16.40').
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The minimum cable length through the CMA is 3 m (9.83’)
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When adding more than two expansion enclosures, you may need to purchase additional cables, depending upon
number of enclosures and cabling method used.
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You may need to order additional or longer cables when cabling a fault-tolerant configuration.
SAS topology
It is possible to support different topologies of SAS with the 4U106 enclosure. There are two basic forms of expansion
topology as shown in
. One is a simple daisy chain of enclosures one after another in a chain (left
illustration). The other topology is a star configuration (right illustration) that has each expansion enclosure connected
from the host (server attached JBOD configuration) or controller enclosure (EBOD configuration).
A third example provided in
, shows use of all SAS ports via the daisy chain cabling method.
