Rapid Spanning Tree Protocol (Rstp) - Allied Telesis SwitchBlade x908 Series Software Reference Manual

Spanning Tree Introduction: STP, RSTP, and MSTP
Command
Configure Root Guard
The Root Guard feature makes sure that the port on which it is enabled is a designated port. If the Root Guard
enabled port receives a superior BPDU, it goes to a Listening state (for STP) or discarding state (for RSTP and MSTP).
interface
awplus(config)#
spanning-tree guard root
awplus(config-if)#
awplus(config-if)# exit
exit
awplus(config)#
Check STP configuration
awplus# show spanning-tree [interface
<port-list>]
Advanced For most networks the default settings for path costs will be suitable, however, you can
configuration: configure them if required

Rapid Spanning Tree Protocol (RSTP)

RSTP uses the process described in
A spanning tree running in STP mode can take up to one minute to rebuild after a topology or
configuration change. The RSTP algorithm provides for a faster recovery of connectivity
following the failure of a bridge, bridge port, or a LAN. RSTP provides rapid recovery by
including port roles in the computation of port states, and by allowing neighboring bridges to
explicitly acknowledge signals on a point-to-point link that indicate that a port wants to enter
the forwarding mode.
In rapid mode, the rapid transition of a port to the forwarding state is possible when the port is
considered to be part of a point-to-point link, or when the port is considered to be an edge
port. An edge port is one that attaches to a LAN that has no other bridges attached.
18.6
<port-list>
(spanning-tree
Software Reference for SwitchBlade® x908, x900 and x600 Series Switches
TM
AlliedWare Plus Operating System - Software Version 5.3.1
Description
Enter Interface Configuration mode for the switch
ports you want to enable Root Guard for.
Enable the Guard Root feature for these ports.
Return to Global Configuration mode.
Return to Privileged Exec mode.
Display the spanning tree configuration for the
device, and confirm the new root bridge priority
(Bridge Priority).
Note that the Bridge ID is in a form like this:
80000000cd240331, and that other IDs follow the
same pattern. This is made up of:
8000—the devices' root bridge priority in
■
hexadecimal
0000cd240331—the devices' MAC address.
■
path-cost).
Table 18-1 to avoid loops.
C613-50007-01 REV B