Redundant Drive Channel Pair - IBM DCS3860 Installation, User's, And Maintenance Manual

8. Connect one end of a SAS cable to the In (↑) SAS connector 1 on the ESM
9. Repeat steps 2 on page 47 through 8 to add more EXP3800 expansion
ESM
ESM
ESM
ESM
Figure 22. Adding enclosures

Redundant drive channel pair

Each storage controller on the DCS3860 storage system has a drive expansion
channel that contains two x4 SAS ports. The storage expansion enclosures that are
connected to this connector form a drive channel. The maximum number of drives
that can be installed is 360. In DCS3860, one drive channel from each controller
combines to form a redundant drive-channel pair. If any component of the drive
channel fails, the controllers can still access the storage enclosures in the redundant
drive-channel pair.
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IBM System Storage DCS3860 Storage System: Installation, User's, and Maintenance Guide
located in slot B of the earlier/last EXP3800 expansion enclosure and connect
the other end of the SAS cable to the Out (↓) SAS connector on the ESM located
in slot B of the EXP3800 expansion enclosure you want to add.
enclosures. You can add up to five expansion enclosures.
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