IBM 7133 D40, Operator'S Manual

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Disk Drive Status lights
These 16 green lights show the status of the disk drives that are installed in
the 7133 unit. The upper row of lights relate to the disk drives that are installed
at the front of the unit, 1 through 8, from left to right. The lower row represents
the disk drives that are installed at the back of the unit, 9 through 16, from
right to left.
Each status light shows the following conditions:
Permanently on
Both SSA links to the disk drive are active, and the disk drive is ready
to accept commands from the using system.
Off Both SSA links to the disk drive are inactive because of one of the
following conditions:
v
The disk drive modules, dummy disk drive modules, or SSA
adapters that should be connected to each side of this module are
missing or not connected.
v
The disk drive modules or dummy disk drive modules that are
connected to each side of this module are inactive.
v
An SSA adapter in the same SSA loop as this module is inactive.
v
A power-on self-test (POST) is running on this disk drive.
Slow flash (two seconds on, two seconds off)
Only one of the SSA links to this disk drive module is active.
Fast flash (five times per second)
This disk drive module is active with a command in progress.
Disk Drive Module Lights
To see the lights on disk drive modules installed in the front part of a 7133 Model D40
or T40 unit:
v
For a Model D40, open the front cover by pivoting it downward
v
For a Model T40, open the front cover by:
1. If necessary, unlocking the cover using the key provided
2. Gripping the front cover on the right and pivoting it to the left.
Chapter 1. Using the Subsystems
7