beautypg.com

Allied Telesis AT-S63 User Manual

Page 499

background image

AT-S63 Management Software Command Line Interface User’s Guide

Section V: Spanning Tree Protocols

499

forwarddelay

Specifies the waiting period before a bridge changes to

a new state, for example, becomes the new root bridge
after the topology changes. If the bridge transitions too
soon, not all links may have yet adapted to the change,
resulting in network loops. The default is 15 seconds.
This parameter effects only those ports operating in the
STP compatible mode.

maxage

Specifies the length of time, in seconds, after which

stored bridge protocol data units (BPDUs) are deleted
by the bridge. All bridges in a bridged LAN use this
aging time to test the age of stored configuration
messages called bridge protocol data units (BPDUs).
For example, if you use the default value of 20, all
bridges delete current configuration messages after 20
seconds. The range of this parameter is 6 to 40
seconds. The default is 20 seconds.

Note

The value for the maxage parameter must be greater than
(2 x (hellotime +1)) and less than (2 x (forwarddelay -1)).

maxhops

Specifies the maximum hops counter. MSTP regions
use this parameter to discard BPDUs. The Max Hop
counter in a BPDU is decremented every time the
BPDU crosses a bridge within a MSTP region. After the
counter reaches zero, the BPDU is deleted. The counter
is reset to its original value if the BPDU crosses a MSTP
regional boundary.

configname

Specifies the name of the MSTP region. The range is 0

(zero) to 32 alphanumeric characters. The name is
case-sensitive and must be the same on all bridges in a
region. Examples include Sales Region and Production
Region. The name must be enclosed in quotes.

revisionlevel

Specifies the reversion number of an MSTP region. The
range is 0 (zero) to 255. This is an arbitrary number that
you assign to a region. The reversion level must be the
same on all bridges in a region. Different regions can
have the same reversion level without conflict.

Description

This command configures the following MSTP parameter settings.

ˆ

Hello time

ˆ

Forwarding delay

ˆ

Maximum age time