Allied Telesis AlliedWare Plus Operating System Version 5.4.4C (x310-26FT,x310-26FP,x310-50FT,x310-50FP) User Manual
Page 488
Spanning Tree Introduction: STP, RSTP, and MSTP
Software Reference for x310 Series Switches
18.20
AlliedWare Plus
TM
Operating System - Version 5.4.4C
C613-50046-01 REV A
Configure MSTP region, revision, and instances
All MSTP devices in this region of the network must have the same region name, revision number, and VLAN to
MSTI mappings.
awplus(config)#
spanning-tree mst configuration
Enter MST Configuration mode.
awplus(config-mst)#
Specify the MSTP region. The region-name parameter is
an arbitrary string that specifies the name you want to
assign to the MST region for identification.
awplus(config-mst)#
The revision-number parameter specifies the revision of
the current MST configuration. The revision is an
arbitrary number that you assign to an MST region. It can
be used to keep track of the number of times that MST
configuration has been updated for the network.
Specify the MST revision number in the range 0 to 255.
awplus(config-mst)#
To allow MSTP to block traffic for different VLANs in
different places in a loop, create multiple MSTP instances
and associate VLANs with them. Each VLAN can only be
in one instance.
Specify the MST instance ID in the range 1 to 15.
Advanced configuration
The commands above are the minimum required to configure MSTP. The following commands allow more
advanced configuration.
Assign root bridge priorities
MSTP lets you distribute traffic more efficiently across a network by blocking different links for different VLANs.
You do this by making different devices into the root bridge for each MSTP instance, and for the CIST, so that
each instance blocks a different link. By default, all devices have the same root bridge priority, 32768 (8000 in
hexadecimal), so the device with the lowest MAC address becomes the root bridge. If you want the device to be
the root bridge for an instance or for the CIST, set the priority to a lower value (a higher priority) than other
devices for this instance. (If you enter a number that is not a multiple of 4096, the device rounds the number
down.)
awplus(config)#
spanning-tree mst configuration
Enter MST Configuration mode.
awplus(config-mst)#
Set the priority for the device to become the root bridge
for each instance.
Specify the MST instance ID in the range 1 to 15.
Specify the root bridge priority in the range 0 to 61440. If
you enter a number that is not a multiple of 4096, the
switch rounds the number down.
awplus(config-mst)#
Return to Global Configuration mode.
Table 18-9: Configuration procedure for MSTP(cont.)