Spanning Tree Commands
©2008 Allied Telesis Inc. All rights reserved.
Software Version 5.2.1
AlliedWare Plus
TM
Operating System Software Reference C613-50003-00 REV E
19.27
spanning-tree forward-time
Use this command to set the forward delay.
The forward delay sets the time (in seconds) to control how fast a port changes its spanning
tree state when moving towards the forwarding state. If the mode is set to STP, the value
determines how long the port stays in each of the listening and learning states which precede
the forwarding state. If the mode is set to RSTP or MSTP, this value determines the maximum
time taken to transition from discarding to learning and from learning to forwarding.
This value is used only when the switch is acting as the root bridge. Switches not acting as the
Root Bridge use a dynamic value for the forward delay set by the root bridge. The forward
delay, maxage, and hello time parameters are interrelated.
Syntax
spanning-tree forward-time <
forward-delay
>
no spanning-tree forward-time
Mode
Configure mode
Default
The default value is 15 seconds.
Usage
The allowable range for forward-time is 4-30 seconds.
The forward delay, maxage, and hello time parameters should be set according to the following
formulae, as specified in IEEE Standard 802.1d:
2 x (forward delay - 1.0 seconds) >= maxage
maxage >= 2 x (hello time + 1.0 seconds)
Example
Related Commands
show spanning-tree
spanning-tree forward-time <forward-delay>
spanning-tree hello-time <hello-time>
spanning-tree mode
Parameter
Description
<
forward-delay
<4-30> the forwarding time delay in seconds.
awplus#
configure terminal
awplus(config)#
spanning-tree forward-time 6