Disk Crossover Pca Replacement Procedure (Nt6M72Xx/6M93Xx); Disk Crossover Pca Replacement - Nortel DMS-10 Series Quick Reference Manual

Disk Crossover PCA Replacement

Procedure (NT6M72xx/6M93xx)
Procedure 4
Disk Crossover PCA replacement (NT6M72xx or NT6M93xx)
Step
CAUTION
Since all BMC PCAs are static sensitive, be careful when
handling them. Wear a wrist grounding strap when working
with the BMC.
WARNING
Since the BMC is powered up during this procedure,
observe all safety procedures for operations on live equip-
ment.
1 Make sure no polling is occurring. Wait for a low traffic period,
if possible.
2 Locate the failing Disk Crossover PCA and change the disk
mode to the other disk ONLY mode, if necessary. The other
disk is the one not in the same chassis as the suspected Disk
Crossover PCA. Enter (at the terminal):
>DISK MODE xx (cr)
where: xx = disk mode = AO = A ONLY
Proper response:
(or)
DISK MODE: AO
3 Place the BMC into an ONLY processor mode. The processor
mode should be the same as the DISK mode. At the Switch and
Status Panel of the BMC:
a. Press the A/B Select Switch to match the active disk drive.
b. Press the O/P Mode Select Switch to O.
c. Turn the Mode Switch to the right and release.
4
Loosen the slotted screws which fasten the outer edges of the
appropriate rear panel assembly to the cabinet.
5 Pull the rear panel away from the cabinet. Remove the front
panel of the chassis to improve cooling, if necessary. Put the
two panels in a safe place to prevent bending and scratching
6 Loosen the 2 screws at the top of the hinged card panel and the
screw at the bottom of the hinged card panel. Let it swing
slowly down from the top until it rests.
Description
= BO = B ONLY
DISK MODE: BO
BMC II AMAT Quick Reference Guide
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