1-43
z The rapid transition feature can be enabled on only root ports or alternate ports.
z If you configure the rapid transition feature on a designated port, the feature does not take effect on
the port.
MSTP Maintenance Configuration

Introduction

In a large-scale network with MSTP enabled, there may be many MSTP instances, and so the status of
a port may change frequently. In this case, maintenance personnel may expect that log/trap information
is output to the log host when particular ports fail, so that they can check the status changes of those
ports through alarm information.

Enabling Log/Trap Output for Ports of MSTP Instance

Follow these steps to enable log/trap output for ports of MSTP instance:
To do... Use the command... Remarks
Enter system view system-view —
Enable log/trap output
for the ports of a
specified instance
stp [ instance
instance-id ] portlog
Required
By default, log/trap output is disabled for the
ports of all instances.
Enable log/trap output
for the ports of all
instances stp portlog all
Required
By default, log/trap output is disabled for the
ports of all instances.

Configuration Example

# Enable log/trap output for the ports of instance 1.
<Sysname> system-view
[Sysname] stp instance 1 portlog
# Enable log/trap output for the ports of all instances.
<Sysname> system-view
[Sysname] stp portlog all
Enabling Trap Messages Conforming to 802.1d Standard
A switch sends trap messages conforming to 802.1d standard to the network management device in the
following two cases:
z The switch becomes the root bridge of an instance.
z Network topology changes are detected.