IBM DS3950, Installation, User'S, And Maintenance Manual, Page: 151 / 252

Attention: Never remove a controller unless the Service Action Allowed
status LED is turned on. Doing so can result in a potential loss of data.
2.
Locate the failed controller by checking the Needs Attention status LEDs on
the controllers in the storage subsystem.
3. Is the Service Action Allowed status LED turned on?
v
Yes – Go to step 4.
v No – Another component might require attention before you can remove
the controller. Use the Recovery Guru function in the DS3950 Subsystem
Management window to identify and correct any additional failures. If there
are none, proceed with step 4 to replace the controller.
Electrostatic discharge can damage sensitive components. Touching the storage
subsystem or its components without using a proper ground might damage
the equipment. To avoid damage, use proper antistatic protection while
handling any components.
4.
Put on antistatic protection.
5. Unpack the new controller. Save all packing materials in the event you need
to return the new controller.
6. Determine whether the replacement controller will serve as controller A or
controller B (controller A is inserted in the left controller bay; controller B is
inserted in the right controller bay), and then apply the controller labels for
host channels, drive channels, and numeric display to the replacement
controller. The controller labels and instructions are included with the
replacement controller. Make sure that the labels are aligned properly and do
not cover any ports or LEDs.
Statement 3:
CAUTION:
When laser products (such as CD-ROMs, DVD drives, fiber-optic devices,
or transmitters) are installed, note the following:
v Do not remove the covers. Removing the covers of the laser product could
result in exposure to hazardous laser radiation. There are no serviceable
parts inside the device.
v
Use of controls or adjustments or performance of procedures other than
those specified herein might result in hazardous radiation exposure.
DANGER
Some laser products contain an embedded Class 3A or Class 3B laser
diode. Note the following.
Laser radiation when open. Do not stare into the beam, do not view
directly with optical instruments, and avoid direct exposure to the beam.
Class 1 Laser statement
Chapter 5. Replacing components
123