Description

The Intention of the article is to provide workaround when we observe alarm on Fan Tray for the PTX10008 box before proceeding for RMA for FAN TRAY and FTC(Fan Tray Controller). Normally we may try to re-seat the fan tray to clear the alarm or replace the Fan Tray or FTC  . However, the alarm may persist even after the RMA in certain situations. 




 

Symptoms

The below alarms may be seen on the device. 

RE0> show chassis alarms 
Aug 15 07:37:46
2 alarms currently active
Alarm time               Class  Description
2023-08-15 06:35:06 UTC  Minor  Fan Tray 0 Set Speed Error
2023-08-15 06:35:02 UTC  Major  Fan Tray 0 is not present

Even after RMA of FTC and Fan tray below alarm may be present.  
RE0> show chassis alarms 
1 alarms currently active
Alarm time               Class  Description
2023-08-15 06:35:06 UTC  Minor  Fan Tray 0 Set Speed Error

Solution

The above alarms still being active after reseat of FTC and FAN TRAY and even RMA indicates a possible issue with the CB itself . In order to confirm if the alarms is indeed a cause of bad CB we can perform the below steps in Service Impacting MW . 

1. Switchover the mastership to the other CB1 and see if the alarm gets cleared or not. 
 

RE0> request chassis routing-engine master switch 
Toggle mastership between routing engines ? [yes,no] (no) yes 

RE1> show chassis alarms 
1 alarms currently active
Alarm time               Class  Description
2023-09-01 05:44:22 UTC  Minor  Backup RE Active<--Upon Mastership switch Alarms seems to have cleared.

2. Deactivate GRES and NSR on the Master Routing Engine.
3. Halt the other RE first and then offline the other CB.On the PTX10008 even though RE is built-in CB we still have to first HALT RE and then offline CB. 
4. Request before to have a Tech on site who can Reseat the CB.
5. Once the Reseat is completed and the CB comes back online.Activate the GRES and NSR back and switch the Mastership back to the other RE.

RE0> show chassis alarms 
No alarms currently active<--Alarms have not re-appeared . 

6. In case if the alarm re-appears again then it could be a faulty CB itself and might need to RMA the CB.
7. If the alarm is present when we perform Step 1 and follows to the other CB as well then the issue needs to be further investigated.


 

Modification History

Initial Draft