Addressing Common Spanning Tree Problems - HP ProCurve Secure 7000dl Series Basic Management And Configuration Manual

C a u t i o n
Table 10-4. Spanning Tree debug Commands
View
general messages
messages when configuration changes occur
periodic hellos and messages when a change in
topology occurs
all BPDUs received
all BPDUs transmitted
all BPDUs transmitted and received
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.
The debug spanning-tree events and debug spanning-tree bpdu
commands are particularly draining on the processor.
You can also use the BPDU debug commands to determine whether interfaces
are actually participating in the spanning tree. If interfaces are not receiving
BPDUs at all, you should check the running-config for an inadvertently applied
BPDU guard or filter.

Addressing Common Spanning Tree Problems

Problems with spanning tree include slow convergence and routers selecting
the wrong primary connection.
Some problems may be caused by other switches on the local network.
You can view information that will help you troubleshoot with this enable
mode command:
Syntax: show spanning-tree [<bridge group number>] [realtime]
Bridging—Transmitting Non-IP Traffic or Merging Two Networks
Troubleshooting Spanning Tree
Command Syntax
debug spanning-tree general
debug spanning-tree config
debug spanning-tree events
debug spanning-tree bpdu receive
debug spanning-tree bpdu transmit
debug spanning-tree bpdu all
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