Article Detail

Description

Backup Routing Engine returns the value 6 (6=down) for the FAN, even though the FAN’s are UP. This article provides the example command output, work-around, and solution.

Symptoms

When an SNMP poll is performed for the fan OID, 1.3.6.1.4.1.2636.3.1.13.1.6, the backup routing engine returns the value 6 (6=down) for the FAN, even though the FANs are UP.

Example Output Showing the Behavior:

Fan Environment:

labroot@> show chassis environment | match fan                
Fans  Top Fan 1                      OK         Spinning at normal speed
      Top Fan 2                      OK         Spinning at normal speed
      Top Fan 3                      OK         Spinning at normal speed
      Top Fan 4                      OK         Spinning at normal speed
      Top Fan 5                      OK         Spinning at normal speed
      Top Fan 6                      OK         Spinning at normal speed
      Top Fan 7                      OK         Spinning at normal speed
      Top Fan 8                      OK         Spinning at normal speed
      Top Fan 9                      OK         Spinning at normal speed
      Bottom Fan 1                   OK         Spinning at normal speed
      Bottom Fan 2                   OK         Spinning at normal speed
      Bottom Fan 3                   OK         Spinning at normal speed
      Bottom Fan 4                   OK         Spinning at normal speed
      Bottom Fan 5                   OK         Spinning at normal speed
      Bottom Fan 6                   OK         Spinning at normal speed
      Bottom Fan 7                   OK         Spinning at normal speed
      Bottom Fan 8                   OK         Spinning at normal speed
      Bottom Fan 9                   OK         Spinning at normal speed

OID Output Status Values:

1- Unknown
2- Up and running
3- Ready to run, not running yet
4- Held in reset, not ready yet
5- Running at Full Speed (valid for fans only)
6- Down or off (for power supply)
7- Running as a standby (Backup)

FAN shows a value of 2 (Running), when an snmpwalk is run from the primary RE0:

labroot> show snmp mib walk 1.3.6.1.4.1.2636.3.1.13.1.6 
jnxOperatingState.1.1.0.0 = 2
jnxOperatingState.2.1.0.0 = 2
jnxOperatingState.4.3.1.0 = 2
jnxOperatingState.4.3.2.0 = 2
jnxOperatingState.4.3.3.0 = 2
jnxOperatingState.4.3.4.0 = 2
jnxOperatingState.4.3.5.0 = 2
jnxOperatingState.4.4.1.0 = 2
jnxOperatingState.4.4.2.0 = 2
jnxOperatingState.4.4.3.0 = 2
jnxOperatingState.4.4.4.0 = 2

FAN shows a value of 6 (Down) , when an snmpwalk is run from the Backup RE1:

{backup:1}
labroot@j> show snmp mib walk 1.3.6.1.4.1.2636.3.1.13.1.6 
jnxOperatingState.4.3.1.0 = 6    
jnxOperatingState.4.3.2.0 = 6     
jnxOperatingState.4.3.3.0 = 6    
jnxOperatingState.4.3.4.0 = 6     
jnxOperatingState.4.3.5.0 = 6     
jnxOperatingState.4.4.1.0 = 6    
jnxOperatingState.4.4.2.0 = 6     
jnxOperatingState.4.4.3.0 = 6     
jnxOperatingState.4.4.4.0 = 6

Solution

Work-around: Poll the OID's only on the primary RE.

For a permanent fix, upgrade the Junos OS to 15.1R8 or later. Refer to the fixed versions in PR1360962 . The code change was done to display the proper value 1 (1-Unknown) which means unknown state.