Multiple Instance Spanning-Tree Operation

Troubleshooting an MSTP Configuration

ProCurve(config)# show spanning-tree debug-counters instance 2 ports a15

Status and Counters - MSTI Port(s) Debug Counters Information

MST Instance

ID : 2

 

 

Port : A15

 

 

 

Counter Name

 

Value

Last Updated

Starved---------------------------MSTI

MSGs

----------

-----------------

0

 

Exceeded Max

Hops MSTI MSGs

0

02/09/07 17:40:59

Topology Changes Detected

1

Topology Changes Tx

3

02/09/07 17:41:03

Topology Changes Rx

2

02/09/07 17:41:01

MSTI MSGs Tx

 

5

02/09/07 17:41:03

MSTI MSGs Rx

 

173489

02/13/07 18:03:52

Figure 4-28. Example of show spanning-tree debug-counters instance ports Command Output for One Port in an MST Instance

 

Field Descriptions in MSTP Debug Command Output

 

Table 4-1contains descriptions of the debugging information displayed in the

 

output of show spanning-tree debug-counters commands.
Table 4-1. MSTP Debug Command Output: Field Descriptions

 

 

Field

Description

 

 

Invalid BPDUs

Number of received BPDUs that failed standard MSTP (802.1Q-REV/D5.0 14.4) validation

 

checks and were dropped. This counter is maintained by the CIST (default MST instance 0)

 

on a per-port basis.

 

 

Errant BPDUs

Number of received BPDUs that were dropped on a port that is configured to not expect

 

BPDU packets. This counter is maintained by the CIST (default MST instance 0 in the

 

network) on a per-port basis and is incremented each time a BPDU packet is received on

 

a port configured with the BPDU filter to ignore incoming BPDU packets (spanning-tree

 

bpdu-filtercommand) or the BPDU protection feature to disable the port when BPDU

 

packets are received (spanning-treebpdu-protectioncommand).

 

 

4-66