Juniper M120 - Page 229

CAUTION: Beforeyou replacea CB, you must take the host subsystem offline.
If there is only one host subsystem, taking the host subsystem offline shuts
down the router. See “Taking the M120 Host Subsystem Offline” on page 267.
CAUTION: If the CB to be replaced is associated with the Routing Engine
currently functioning as the master Routing engine, switch it to the backup
before removing the CB. See “Taking the M120 Host Subsystem Offline” on
page 267.
To remove a CB (see Figure 74 on page 204):
1. Take the host subsystem offline. See “Taking the M120 Host Subsystem Offline” on
page 267.
2. Place an electrostatic bag or antistatic mat on a flat, stable surface.
3. Attach an ESD grounding strap to your bare wrist and connect the strap to one of the
ESD points on the chassis.
4. Loosen the captive screws on the ejector handles, using a Phillips (+) screwdriver,
number 2.
5. Simultaneously rotate the ejector handles counterclockwise to unseat the CB.
6. Grasp the ejector handles and slide the CB about halfway out of the chassis.
7. Place one hand underneath the CB to support it and slide it completely out of the
chassis.
8. Place the CB on the antistatic mat.
9. If you are not replacing the CB now, install a blank panel over the empty slot.
203Copyright © 2018, Juniper Networks, Inc.
Chapter 26: Replacing Host Subsystem Components