Maintaining the Optical ILA Cooling System
Removing a Fan Module from an Optical ILA
The fan modules in an optical ILA are hot-removable and hot-insertable field-replaceable units (FRUs)—you can remove and replace them without powering off the optical ILA or disrupting optical ILA functions.
Replace the fan module within 30 seconds of removal to prevent chassis overheating. Before removing the fan module, ensure that you have a replacement fan module available.
Before you remove a fan module from an optical ILA, ensure that you have taken the necessary precautions to prevent electrostatic discharge (ESD) damage (see Prevention of Electrostatic Discharge Damage).
Ensure that you have the following parts and tools available:
ESD grounding strap
Antistatic bag or an antistatic mat
Phillips (+) screwdriver, number 2
To remove a fan module from an optical ILA (see Figure 1):
- Place the antistatic bag or the antistatic mat on a flat, stable surface.
- To prevent damage to the equipment caused by static discharge, attach an ESD grounding strap to your bare wrist, and connect the strap to one of the ESD points on the chassis.
- Using a screwdriver, loosen the captive screws on the side of the fan.
- Grasp the large captive screws on the fan module to slide
the fan module halfway out of the chassis.
Warning To avoid injury, do not touch the fan with your hands or any tools as you slide the fan module out of the chassis—the fan might still be running.
- When the fan stops rotating, slide the fan module completely out of the chassis.
- Place the fan module in the antistatic bag or on the antistatic mat placed on a flat, stable surface.

When a fan module is removed, the system raises an alarm. You can enter the show alarm CLI command to view the message.
Installing a Fan Module in an Optical ILA
The fan modules in an optical ILA are hot-removable and hot-insertable field-replaceable units (FRUs)—you can remove and replace them without powering off the optical ILA or disrupting routing functions.
Replace the fan module within 30 seconds of removal to prevent chassis overheating. Before removing the fan module, ensure that you have a replacement fan module available.
The fan module provides airflow out, which is also known as front-to-back airflow.
Before you install a fan module in an optical ILA, ensure that you have taken the necessary precautions to prevent electrostatic discharge (ESD) damage (see Prevention of Electrostatic Discharge Damage ).
Ensure that you have the following parts and tools available:
ESD grounding strap
Phillips #2 (+) screwdriver
To install a fan module in an optical ILA (see Figure 2):
- To prevent damage to the equipment caused by static discharge, attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to one of the ESD points on the chassis.
- Taking care not to touch the connectors, remove the fan module from its bag.
- Align the module with the open slot on the FRU end of the optical ILA and slide it in until it is fully seated.
- Use a screwdriver to secure the captive screws tightly on each side.

