21205 Board Fault

Description

This alarm is generated on the SCU in the GMPS when the communication between the board and the SCU in the GMPS is interrupted.

Attribute

Alarm ID	Alarm Severity	Alarm Type
21205	Critical	Fault

Parameters

ID	Name	Meaning
1	Subrack No.	Number of the subrack where the board is generated
2	Slot No.	Number of the slot where the board is generated
3	Board Type	0=GOMU,1=GSCU,2=GGCU,3=GEIU/GOIU,4=GTNU,5=GXPUx,6=GDPUx,7=GF2/GOU/PEU
4	Alarm Attribute	0=Normal, Alarms period are longer than the Transient Threshold. 1=Transient Count, The times and the period of the alarms whose periods are shorter than the Transient Threshold are summed up. If the sum result is longer than the Alarm Occurrence Period Threshold or Alarm Occurrence Times Threshold, an alarm so called Transient Count Alarm is triggered. Because Transient Count Alarm is based on accumulative result, the recovery of the alarm may occur at least one Summing Cycle later. The Summing Cycle can be query by MML "LST STATSLDWIN".

Impact on the System

GOMU:

The board cannot be maintained.
If the alarm is generated because the OMU software is stopped, the external IP address is released. In such a case, if no physical IP address is configured, operations cannot be performed to the BSC through the network remotely.
If the alarm is generated because the backup channel is faulty, then the function of GOMU backup does not take effect, the function of GOMU switchover does not take effect, and the system performance deteriorates.

Boards other than GOMU:

The board cannot be maintained.
The board for which the alarm is generated does not provide services. If the board works in active/standby mode, the active board takes over the services on the standby board. If the board does not work in active/standby mode, services on the board are interrupted.
If the alarm is generated because the Ethernet cable between subracks is disconnected, the services may be interrupted.

System Actions

None.

Possible Causes

If the GOMU is faulty, the possible causes are as follows:

A pair of GOMUs is configured for the BSC, but only one GOMU is operating.
A pair of GOMUs is configured for the BSC, but on the operating standby GOMU, the OMU software is stopped or the startup of the OMU software fails.
A pair of GOMUs is configured for the BSC, but the standby GOMU is reset.
A pair of GOMUs is configured for the BSC and the OMU software on the operating standby GOMU runs normally, but the communication link between the active GOMU and the standby GOMU is faulty.

If the board other than the GOMU is faulty, the possible causes are as follows:

If all boards in a subrack are faulty, the Ethernet cable between this subrack and the GMPS may be disconnected.
If all boards in the TC subrack are faulty, the OML on the Ater interface may be disconnected or the Ethernet cable between the main subrack and the extension subrack may be disconnected.
If an individual board in a subrack is faulty, the board may be manually removed from the subrack, switched over, or reset.
If an individual board in a subrack is faulty, the board is reset because hardware or software fault occurs on the board.

Procedure

GOMU:

On the LMT, check whether a pair of GOMUs is configured for the BSC.
Y => Go to 2.

N => Contact Huawei Customer Service Center.
Check whether the standby GOMU is powered on and started.
Y => Go to 3.

N => Insert the standby GOMU. Then, wait until the startup of the GOMU is complete. Go to 4.
Check whether the standby GOMU is in the resetting process.
Y => Wait until the startup of the GOMU is complete. Go to 6.

N => Go to 4.
Check whether the OMU software on the standby GOMU is started.
Y => Contact Huawei Customer Service Center.

N => Start the OMU software on the standby GOMU. Then, check whether the alarm is cleared.
Check whether the alarm is cleared.
Y => The alarm handling is complete.

N => Contact Huawei Customer Service Center.

Boards other than the GOMU:

If the remote TC subrack is configured, check whether the OML on the Ater interface is disconnected.
1. On the LMT, check whether the remote configuration is adopted and whether all boards in the TC subrack are unavailable.
  Y => Go to b.
  
  N => Go to 2.
2. Log in to the LMT. Choose Alarm Maintenance > Browse Alarm to check whether the following parent alarm is reported.
  21551 Ater OML Broken Alarm
  
  Y => Go to c.
  
  N => Go to 2.
3. If the alarm is reported, rectify the fault according to the alarm help. Then, check whether the alarm is cleared.
  Y => The alarm handling is complete.
  
  N => Go to 2.
Check whether the Ethernet cable between SCUs of the GMPS and another subrack is disconnected.
1. On the LMT, check whether all boards in the subrack are unavailable.
  Y => Go to b.
  
  N => Go to 3.
2. Check whether the port on panel of the SCU in the GMPS is enabled.
  Y => Go to d.
  
  N => Enable the port on the panel. Go to c.
3. Check whether the alarm is cleared.
  Y => The alarm handling is complete.
  
  N => Go to d.
4. Check whether the Ethernet cable between the SCUs on the GMPS and the problematic subrack is normal and whether the Ethernet port LED is normal.
  Y => Contact Huawei Customer Service Center.
  
  N => Replace the Ethernet cable. Go to 4.
Check whether the board is faulty.
1. On the LMT, check whether the board is being loaded. After the board is successfully loaded, check whether the alarm is cleared.
  Y => The alarm handling is complete.
  
  N => Go to b.
2. Check whether the board is removed. Insert the board and wait until the loading of the board is complete. Then, check whether the alarm is cleared.
  Y => The alarm handling is complete.
  
  N =>Go to c.
3. Remove and then reinsert the board when the traffic volume is low. Then, check whether the alarm is cleared.
  Y => The alarm handling is complete.
  
  N => Go to d.
4. Replace the board. Then, check whether the alarm is cleared.
  Y => The alarm handling is complete.
  
  N => Contact Huawei Customer Service Center.
Check whether the alarm is cleared.
Y => The alarm handling is complete.

N => Contact Huawei Customer Service Center.