Reference Guide

MST region name
and revision
The congured name and revisions must be identical among all devices. If the region name is blank, a name was
congured on one device and was not congured or was congured dierently on another — spelling and
capitalization counts.
MST instances Verify the VLAN to MST instance mapping using the show commands. If you see extra MST instances in the
Sending or Received logs, an additional MST instance was congured on one router but not others.
• View BPDUs in EXEC mode.
debug spanning-tree bpdu
• View MST-triggered topology change messages in EXEC mode.
debug spanning-tree events
View MST conguration
OS10# show spanning-tree mst configuration
Region Name: force10
Revision: 100
MSTI VID
0 1,31-4093
1 2-10
2 11-20
3 21-30
MST commands
debug spanning-tree
Enables STP debug and displays protocol information.
Syntax
debug spanning-tree {all | bpdu [tx | rx] | events}
Parameters
• all — Debugs all spanning tree operations.
• bpdu — Enter transmit (tx) or receive (rx) to enable the debug direction.
• events — Debugs PVST events.
Default Not congured
Command Mode EXEC
Usage Information None
Example
OS10# debug spanning-tree bpdu rx
Supported Releases 10.2.0E or later
spanning-tree mst forward-time
Congures a time interval for the interface to wait in the Blocking state or the Learning state before moving to the Forwarding state.
Syntax
spanning-tree mst forward-time seconds
Parameters seconds — Enter the number of seconds an interface waits in the Blocking or Learning States before moving to
the Forwarding state (4 to 30).
Default 15 seconds
176 Layer 2