Lenovo DS4200 Product Manual page 12

Each ThinkSystem DS Series Expansion Unit ships with two SAS I/O expansion modules. Each expansion
module provides 12 Gb SAS connectivity to the internal drives, and it has three external 12 Gb SAS x4
ports (Mini-SAS HD SFF-8644 connectors labelled Port A, Port B, and Port C) that are used for
connections to the ThinkSystem DS4200 and for daisy chaining the expansion enclosures between each
other.
The expansion port on the controller module is connected to the Port A on the expansion module, and the
Port C on the expansion module is connected to the Port A on the expansion module in the adjacent
enclosure, and so on.
Note: The Port B on the expansion module is not used.
The expansion enclosure connectivity topology is shown in the following figure.
Figure 7. Expansion unit connectivity topology
The following table lists ordering information for the supported expansion enclosure connectivity options.
Table 7. Expansion unit connectivity options
Description
External MiniSAS HD 8644/MiniSAS HD 8644 0.5M Cable
External MiniSAS HD 8644/MiniSAS HD 8644 1M Cable
External MiniSAS HD 8644/MiniSAS HD 8644 2M Cable
External MiniSAS HD 8644/MiniSAS HD 8644 3M Cable
* One cable per expansion module; two cables are required per each expansion enclosure.
Lenovo ThinkSystem DS4200 Storage Array
Part Feature Quantity per one
number code expansion unit
00YL847 AU16 2*
00YL848 AU17 2*
00YL849 AU18 2*
00YL850 AU19 2*
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