0 Replies Latest reply on Mar 1, 2017 8:54 AM by diggly

    Port-Channel between two ActivChassis stacks not working right

    diggly New Member

      I have an Edge stack of 7 1638ps and a Core stack of 2 1638s.  In addition to the ActivChassis stacking modules and cables for each switch, I have stacking modules in both Core switches and VCIDs 3 and 7 in the Edge stack, cabled as:

       

      Core 1/2/1 => Edge 3/2/1
      Core 1/2/2 => Edge 3/2/2
      Core 2/2/1 => Edge 7/2/1
      Core 2/2/2 => Edge 7/2/2

       

      this gives me these results:

       

      Core 1/2/1 => Edge 3/2/1 >>> 1Gb/s, data flowing (web interface shows 1000/Full on Core, 1000/Full on EDGE)

       

      Core 1/2/2 => Edge 3/2/2 >>> 10Gb/s, all packets discarded (web interface shows 10G/ActivChassis on Core, 10G/Full on EDGE)

       

      Core 2/2/1 => Edge 7/2/1 >>> 10Gb/s, all packets discarded (web interface shows 10G/ActivChassis on Core, 10G/Full on EDGE)

       

      Core 2/2/2 => Edge 7/2/2 >>> 10Gb/s, all packets discarded (web interface shows 10G/ActivChassis on Core, 10G/Full on EDGE)

       

      Snippets of the web interface attached.

       

      Could be the web interface just has a display bug but the fact is that no data is flowing on three of the four ports. I don't know how long the switches have been in this state.  I discovered this after parts of the EDGE stack crashed twice in 5 days and I was carefully reviewing the configs.  I have no idea if this would cause a crash, but it certainly looks like something that ought to get fixed.

       

      For now I have created a LAG with 4 gigabit ports and shut the 10Gb interfaces down.

       

      I have a feeling that rebooting the Core switches will clear this up, but that's a non-trivial thing to do and I am looking for some thoughts on whether that will actually help, or if there is another solution.

       

      Thanks.

       

      Config is as follows:

       

      AOS R11.10.5 on both stacks

       

      CORE:
      interface port-channel 1
        description (port-channel 1) LAG to EDGE
        spanning-tree port-priority 64
        no shutdown
        switchport mode trunk

       

      interface xgigabit-switchport 1/2/1
        description (1/2/1) CORE-EDGE LAG-1
        shutdown
        switchport mode trunk
        channel-group 1 mode on
        speed auto

       

      interface xgigabit-switchport 1/2/2
        description (1/2/2) CORE-EDGE LAG-2
        shutdown
        switchport mode trunk
        channel-group 1 mode on
        speed auto

       

      interface xgigabit-switchport 2/2/1
        description (2/2/1) CORE-EDGE LAG-3
        shutdown
        switchport mode trunk
        channel-group 1 mode on
        speed auto

       

      interface xgigabit-switchport 2/2/2
        description (2/2/2) CORE-EDGE LAG-4
        shutdown
        switchport mode trunk
        channel-group 1 mode on
        speed auto

       

      EDGE:
      interface port-channel 1
        description (port-channel 1) LAG to CORE
        spanning-tree port-priority 64
        no shutdown
        switchport mode trunk

       

      interface xgigabit-switchport 3/2/1
        description (3/2/1) CORE-EDGE LAG-1
        shutdown
        switchport mode trunk
        channel-group 1 mode on
        speed auto

       

      interface xgigabit-switchport 3/2/2
        description (3/2/2) CORE-EDGE LAG-2
        shutdown
        switchport mode trunk
        channel-group 1 mode on
        speed auto

       

      interface xgigabit-switchport 7/2/1
        description (7/2/1) CORE-EDGE LAG-3
        shutdown
        switchport mode trunk
        channel-group 1 mode on
        speed auto

       

      interface xgigabit-switchport 7/2/2
        description (7/2/2) CORE-EDGE LAG-4
        shutdown
        switchport mode trunk
        channel-group 1 mode on
        speed auto