Viewing debug counters per-port per-VLAN

Syntax:


show spanning-tree debug ports port-list vlan vlan-id

Displays the aggregate values of all RPVST+ debug counters maintained on one or more ports used by a specified VLAN.

Viewing debug counters for a specific port on a VLAN

Switch_A(config)# show spanning-tree debug ports 9 vlan 20

 Status and Counters - RPVST Debug Counters Information

  VLAN ID : 20
  Port : 9

  Counter Name                   Value           Last Updated
  ------------------------------ --------------- --------------------
  Invalid BPDUs                  0               04/16/2012 22:27:15
  Errant BPDUs                   0               04/16/2012 22:27:15
  Looped-back BPDUs              0               04/16/2012 22:27:15
  Starved BPDUs                  5               05/01/2012 21:48:11
  Exceeded Max Age BPDUs         0               04/16/2012 22:27:15
  Topology Changes Detected      9               05/04/2012 21:54:05
  Topology Changes Tx            5               05/05/2012 22:04:49
  Topology Changes Rx            2               05/07/2012 18:08:34
  Topology Change ACKs Tx        0               04/16/2012 22:27:15
  Topology Change ACKs Rx        0               04/16/2012 22:27:15
  TCN BPDUs Tx                   0               04/16/2012 22:27:15
  TCN BPDUs Rx                   0               04/16/2012 22:27:15
  CFG BPDUs Tx                   0               04/16/2012 22:27:15
  CFG BPDUs Rx                   0               04/16/2012 22:27:15
  RST BPDUs Tx                   0               04/16/2012 22:27:15
  RST BPDUs Rx                   0               04/16/2012 22:27:15
  RPVST BPDUs Tx                 7812            05/05/2012 22:04:49
  RPVST BPDUs Rx                 1065            05/08/2012 19:43:11