Hello,
Today , this post will share with you a case where the Fan State Lights of the OSN3500 Expansion Subrack are Red.
Problem Description
The three fan state lights on the fan box of the OSN3500 expansion subrack on the live network are red, and the network management system has no alarm.
Alarm
Handling Process
Analyzing the alarm process, the possible causes of this problem are as follows:
The main reasons for the fan's red light:
1- Fan alarm (the grid and command line fans have no alarm after verification)
2- The fan box is faulty (after replacing the fan, the fan box has no fault)
3- The PWM provided by the host to the fan box is lower than 15%, or the signal is pulled low. This signal is provided by the XCE board.
At present, the first and second basic exclusions need to focus on the third reason.
The current network application operation window prepares XCE spare parts troubleshooting: There are unused boards in slots 56/57 of the expansion subrack. It is recommended to remove them for fear of interference.
1- Use the following command to query the PWM register of the XCE board, and the result is normal.
:optp:3b,0,77,1,30,08,c6,c6,c6,3c,3c,3c
:optp:3b,0,77,1,d,51,a,0,0,0,1e,1
:optp:3b,0,77,1,d,51,a,0,0,0,18,1
:optp:3b,0,77,1,30,08,e7,e7,e7,a5,a5,a5
:optp:3c,0,77,1,30,08,c6,c6,c6,3c,3c,3c
:optp:3c,0,77,1,d,51,a,0,0,0,1e,1
:optp:3c,0,77,1,d,51,a,0,0,0,18,1
:optp:3c,0,77,1,30,08,e7,e7,e7,a5,a5,a5
2- Manually set the fan speed to high/mid/low (setting the speed will set the PWM value), and observe that the fan status light turns green. It is suspected to be related to the abnormal XCE detection signal.
:cfg-set-fanspeed:high (with high/mid/low parameters, set to auto after the test)
:cfg-get-fanspeed (query result)
3- Pull out the spare XCE and observe the status light unchanged.
4- Observe that there is no pin in the spare XCE slot.
5- Insert the backup XCE, do the XCE master/backup switch, pull out the original master XCE, and find that the fan indicator turns green.
6- Observe that the original active XCE slot does not have a pin inverted, and judge that the active XCE is faulty.
7- After the faulty board is replaced, switch the test again, and the fan indicator shows normal.
Root cause
The main XCE board is faulty, causing the PWM signal provided to the fan box to be less than 15%.
Solution
Replace the XCE board.
Conclusions
It is recommended that services not carried by the device be discovered and handled in time.
You are welcome to leave a message and exchange in the comment area. Thank you!
