Stp Root-Protection - 3Com 7750 Series Command Reference Manual

3Com Switch 7750 Series
Command Reference Guide – MSTP
Description
Use the stp root secondary command to configure the current switch as a secondary
root bridge of a specified spanning tree instance.
Use the undo stp root command to cancel the current configuration.
By default, a switch does not operate as a secondary root bridge.
If you do not specify the instance-id argument, these two commands apply to the CIST.
You can configure one or more secondary root bridges for a spanning tree instance. If
the switch operating as the root bridge fails or is turned off, the secondary root bridge
with the least MAC address becomes the root bridge.
You can also specify the network diameter and the Hello time of the switch that you are
configuring as a secondary root bridge. The switch will then figures out the other two
time parameters: Forward delay and Max age. You can configure only one root bridge
for a spanning tree instance but you can configure one or more secondary root bridges
for a spanning tree instance. Once a switch is configured as the root bridge or a
secondary root bridge, its priority cannot be modified.
Example
# Configure the current switch as a secondary root bridge of spanning tree instance 4,
setting the network diameter of the switched network to 5 and the Hello time to 300
centiseconds.
<3Com> system-view
System View: return to User View with Ctrl+Z.
[3Com] stp instance 4 root secondary bridge-diameter 5 hello-time 300

1.1.38 stp root-protection

Syntax
stp root-protection
undo stp root-protection
View
Ethernet port view
Parameter
None
Description
Use the stp root-protection command to enable the root protection function on the
current port.
Chapter 1 MSTP Configuration Commands
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