Cabletron Systems 9032578-05 manual Adjusting Bridge Protocol Data Unit Bpdu Intervals

Chapter 3: Bridging Configuration Guide

Adjusting Bridge Protocol Data Unit (BPDU) Intervals

You can adjust BPDU intervals as described in the following sections:

•Adjust the Interval between Hello BPDUs

•Define the Forward Delay Interval

•Define the Maximum Idle Interval

Adjusting the Interval between Hello Times

You can specify the interval between hello time.

To adjust this interval, enter the following command in Configure mode:

Specify the interval between hello	stp set bridging hello-time <num>
time for default spanning tree.
Specify the interval between hello	pvst set bridging spanning-tree <string>
time for a particular instance of	hello-time <num>
spanning tree.

Defining the Forward Delay Interval

The forward delay interval is the amount of time spent listening for topology change information after an interface has been activated for bridging and before forwarding actually begins.

To change the default interval setting, enter the following command in Configure mode:

Set the default of the forward delay	stp set bridging forward-delay <num>
interval for default spanning tree.
Set the default of the forward delay	pvst set bridging spanning-tree <string>
interval for a particular instance of	forward-delay <num>
spanning tree.

Defining the Maximum Age

If a bridge does not hear BPDUs from the root bridge within a specified interval, it assumes that the network has changed and recomputes the spanning-tree topology.

30 SmartSwitch Router User Reference Manual