Installation guide

4. The disk drive modules of the 7133 are connected to an SSA attachment, or to
other devices, by way of SSA loops. Before you go any further in these instructions,
read carefully the following notes.
Important Notes:
a. Rules for SSA Loops:
Refer to the user or maintenance manual for your using-system SSA attachment
for the set of rules that you must follow when you configure SSA loops. These
rules ensure that your loops are valid loops.
The manual also contains rules for the physical relationship between disk drive
modules and SSA attachments. These rules help you to get the best
performance from your subsystem.
SSA loops that include the disk drive modules of a 7133 must also follow these
additional rules:
v A maximum of three neighboring dummy disk drive modules can be
connected in a particular SSA loop.
v The maximum permitted length for an external SSA cable that connects two
SSA nodes (for example, disk drives) is 25 meters (82 feet).
v The maximum permitted length for an external fibre optic cable that connects
two SSA nodes (for example, disk drive modules) is 10 kilometers (32800
feet).
Installing and Testing the 7133 Model T40 9
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