•
The ESM connector (In or Out)
•
The drive tray ID
For example, if you are connecting controller A to the SAS In port on ESM A in drive tray 1, the
label on the controller end of the cable has this information:
CtA-Dch1, Dm1-ESM_A (left), In – Controller End
The label on the drive tray end of the cable has information:
Dm1-ESM_A (left), In, CtrlA
If you are connecting an ESM (Out) port to an ESM (In) port, the label on the first drive tray has
information:
Dm1-ESM_A (left), OUT, DM1 ESM_B (left)
E2700 controllers share two expansion SAS domains. The dual expansion ports allow external
bandwidth capability, as each port contains four PHYs on each E2700 controller.
You can connect a controller tray to drive trays using one of these patterns:
•
Single stack
In a single stack pattern the expansion channels from each controller are paired by connecting
them to the same ESM. At least one expansion port from each controller must be connected to
each expansion channel on the ESM. For improved band-width to the expansion trays, connect
two ports from each controller to each expansion channel, one to the top of the stack and the other
to the bottom of the stack.
When there is only one drive tray, connect both controller expansion ports to the SAS IN ports on
the same ESM in a single stack to maximize performance.
•
Dual stack
Dual stack cabling requires that both expansion ports on each controller are used for drive-side
cabling in order to create two logically separate stacks. Compared to single stack, dual stack
delivers the maximum possible bandwidth performance out of expansion enclosure when you
scale beyond one expansion enclosure.
When there is more than one drive tray, use a dual stack pattern to maximize performance. The
intention is to create two stacks, each stack cabled in either a top-down pattern or a bottom up
pattern. When an even number of expansion trays are used, the two stacks should each contain the
same number of expansion trays. When an odd number of expansion trays are used, one stack will
have one more tray than the other.
•
One E2712 or E2724 controller-drive tray and one drive tray in a single stack
88 | E2700 Controller-Drive Tray and Related Drive Trays Installation Guide
Summary of Contents for E2760
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