Command Reference Guide

3Com Router 3000 Ethernet Family
Command Reference Guide Chapter 3 Bridge Configuration Commands
3Com Corporation
3-7
Example
# Set the STP standard supported by a bridge set to IEEE.
[Router] bridge 1 stp ieee
3.1.10 bridge stp max-age
Syntax
bridge stp max-age seconds
undo bridge stp max-age
View
System view
Parameter
seconds: Value for the Max Age timer on the bridge, in the range 6 to 40 seconds. It
defaults to 20 seconds.
Description
Use the bridge stp max-age command to set the Max Age timer on the bridge.
Use the undo bridge stp max-age command to restore the default.
A Max Age timer is used to limit the lifetime of BPDUs. Enabling STP on a port starts a
Max Age timer. If the interface receives no BPDU before the timer expires, its link is
considered faulty and STP starts to recalculate its topology.
When configuring a Max Age timer, consider the following:
z On a spanning tree, all bridges use the Max Age timer of the root instead of their
own.
z Set the timer appropriately. A small timer may result in undesired spanning tree
calculation frequency and have the bridge mistake congestions for link failures. A
large timer, on the contrary, may decrease the self-tuning capability of the network
preventing the bridge from discovering link failures quickly.
You are recommended to use the default Max Age timer setting in normal cases.
Example
# Set the Max Age timer on the bridge to 30 seconds.
[Router] bridge stp max-age 30
3.1.11 bridge stp priority
Syntax
bridge stp priority value