This article explains the incorrect value for the ifStackStatus for the member links of ae bundle and what to collect from the customer device, if it happens.

In a working scenario,

In the below example ae1 bundle has 6 member links. All of them are associated with the ae1.

user@router> show snmp mib walk ifName | match ae1      

ifName.789  = ae1

ifName.790  = ae1.0

user@router> show snmp mib walk ifStackStatus | match 790   

ifStackStatus.0.790 = 1

ifStackStatus.790.785 = 1 <<<< member links indexes and its values. (790 is index of ae1.0)

ifStackStatus.790.786 = 1

ifStackStatus.790.787 = 1

ifStackStatus.790.788 = 1

ifStackStatus.790.1003 = 1

ifStackStatus.790.1013 = 1

In the problematic state the output looks like below:

In the below example ae3 bundle has one member link, however the index of the member link is not reported.

user@router> show snmp mib walk ifName | match ae3 

ifName.695  = ae3

ifName.696  = ae3.0

user@router> show snmp mib walk ifStackStatus | match 696 

ifStackStatus.0.696 = 1

ifStackStatus.696.0 = 2 <<<<< 0 is incorrect value, it should have the member links unit 0 index should be reported.

Please collect the following details from the customer setup, to share with the engineering.

1) Walk output of "show snmp mib walk ifStackStatus | save /var/tmp/ifstack.walk.1"

2) Enable kernel level tracing:

   a) set system syslog file messages kernel any

3) Enable SNMP traceoptions

 set snmp traceoptions flag all

 set snmp traceoptions file size 60m files 6

4) start the following from router shell:

 rtsockmon -rt > /var/tmp/rtsock_logs.txt &

5) Collect snapshot-1 of the following files.

     a) RSI

     b) live-core of mib2d (from shell 'gcore -c /var/tmp/gc.mib2d.1 <PID-of-mib2d>')

     c) All /var/log/* files.

     d) /var/tmp/ifstack.walk.1

6) Restart mib2d process.

7) Walk output of "show snmp mib walk ifStackStatus | save /var/tmp/ifstack.walk.2".

8) Check whether the issue still persists.

  Collect snapshot-2 of logs mentioned in Step-4 (a,b,c), /var/tmp/ifstack.walk.2, /var/tmp/rtsock_logs.txt files.