This alarm is reported when the board-in-position signal is not detected.

Parameters

Parameter Name	Parameter Description
Cabinet No.	Cabinet number of the faulty board
Subrack No.	Subrack number of the faulty board
Slot No.	Slot number of the faulty board
Board Type	Type of the faulty board

Impact on the System

Alarm Severity	Alarm Impact
Major	The board cannot work normally. The ongoing services carried on the board are disrupted.

System Actions

The system automatically disables the board and isolates the board from all other boards.

Possible Causes

·     The board does not exist or is not securely installed.

·     The backplane slot is faulty.

·     The board hardware is faulty.

·     The main control board (in the subrack that houses the board) is not securely installed.

·     The hardware of the main control board is faulty.

·     A redundant board is configured.

Procedure

1.     Check for the redundant board on the M2000.

a.   Y => The redundant board is configured. Go to sub-step b.

N => There is no redundant board. Go to step 2.

b.   Run the MML command RMV BRD to remove the board in the faulty slot.

Check whether the alarm is cleared.

Y => The alarm is cleared. No further action is required.

N => The alarm is not cleared. 

Remove the board and properly reinstall it on site.

c.   Remove and reinstall the board.

Check whether the alarm is cleared.

Y => The alarm is cleared. No further action is required.

N => The alarm is not cleared. Go to step 3.

2.     Check the backplane slot in the BBU on site.

a.   Remove the board. Then, use a flashlight to check whether there is any bent or broken pin in the backplane slot that holds the board.

Y => The backplane slot that holds the board malfunctions. Go to sub-step b.

N => The backplane slot that holds the board is normal. Go to step 4.

b.   Check whether there is another idle backplane slot compatible with the board.

Y => There is another idle backplane slot. Go to sub-step c.

N => There is no idle backplane slot. 

Run the MML command RMV BRD to remove the board in the faulty slot.

c.   Run the MML command ADD BRD to add the board in the idle slot.

d.   Remove the board from the faulty slot and install it in the idle slot. Wait until the board startup is complete (the RUN LED blinking, ON for 1s and OFF for 1s).

Check whether the alarm is cleared.

Y => The alarm is cleared. No further action is required.

N => The alarm is not cleared. Go to step 4.

3.     Replace the faulty board on site.

a.   Replace the board.

Check whether the alarm is cleared.

Y => The alarm is cleared. No further action is required.

N => The alarm is not cleared. Reinstall the original board. Go to step 5.

4.     Remove and properly reinstall the main control board in the subrack that houses the faulty board on site.

a.   Note: Removing or reinstalling the main control board disrupts all the ongoing services of the base station. Therefore, perform this operation in low-traffic hours.

Remove and reinstall the main control board.

Check whether the alarm is cleared.

Y => The alarm is cleared. No further action is required.

N => The alarm is not cleared. Go to step 6.

5.     Replace the main control board in the subrack that houses the faulty board on site.

a.   Note: Replacing the main control board disrupts all the ongoing services of the base station. Therefore, perform this operation in low-traffic hours. The base station software upgrade may be required during board replacement, so the correct software version should be ready for use in advance.

Replace the main control board.

Check whether the alarm is cleared.

Y => The alarm is cleared. No further action is required.

N => The alarm is not cleared. Reinstall the original main control board. 

Well structured & well articulated.

Impressive

useful document, thanks