Viewing debug counters per-VLAN

Syntax:


show spanning-tree debug vlan vlan-id

Displays the aggregate values of all RPVST+ debug counters maintained on a switch for a specified VLAN.

Viewing debug counters for a specific VLAN

switch(config)# show spanning-tree debug vlan 20

 Status and Counters - RPVST Debug Counters Information

  VLAN ID : 20

                                 Aggregated Value
  Counter Name                   Collected from Ports
  ------------------------------ --------------------
  Invalid BPDUs                  5
  Errant BPDUs                   10
  Looped-back BPDUs              0
  Starved BPDUs                  9
  Exceeded Max Age BPDUs         2
  Topology Changes Detected      9
  Topology Changes Tx            4
  Topology Changes Rx            181
  Topology Change ACKs Tx        0
  Topology Change ACKs Rx        0
  TCN BPDUs Tx                   0
  TCN BPDUs Rx                   0
  CFG BPDUs Tx                   0
  CFG BPDUs Rx                   0
  RST BPDUs Tx                   0
  RST BPDUs Rx                   0
  RPVST BPDUs Tx                 1531
  RPVST BPDUs Rx                 1428