10-25
Bridging—Transmitting Non-IP Traffic or Merging Two Networks
Troubleshooting Spanning Tree
Troubleshooting Spanning Tree
This section describes how to test and troubleshoot the router’s spanning tree
functions.
Note You must enter show and debug commands from the enable mode context
or preface the command with do.
Testing Spanning Tree
You can run spanning tree debug commands to test a router’s spanning tree
functions. (Generally, you will not use these debug commands in a live
network.) You can view debug messages to verify that:
■ the router chooses the correct primary connection
■ appropriate interfaces move quickly into the forwarding state
■ when a connection goes down, the network converges within one or two
seconds
The syntax for the debug commands is shown in Table 10-4.
Table 10-4. Spanning Tree debug Commands
The debug spanning-tree events command displays messages dealing with
reconvergence when the network topology changes. When you enter the
debug spanning-tree command with one of the bpdu options, the terminal
displays a message every time an interface sends or receives a BPDU, or both.
View Command Syntax
general messages debug spanning-tree general
messages when configuration changes occur debug spanning-tree config
periodic hellos and messages when a change in
topology occurs
debug spanning-tree events
all BPDUs received debug spanning-tree bpdu receive
all BPDUs transmitted debug spanning-tree bpdu transmit
all BPDUs transmitted and received debug spanning-tree bpdu all
To Next Page
Loading...
Need help?
General
