622
C
38: MSTP C
HAPTER
Examples
stp root secondary
Syntax
View
Parameters
Description
Examples
C
ONFIGURATION
OMMANDS
If you do not provide instance instance-id, your configuration will take effect
■
in the CIST instance only.
There is only one root bridge in effect in a spanning tree instance. If two or
■
more devices have been designated to be root bridges of the same spanning
tree instance, MSTP will select the device with the lowest MAC address as the
root bridge.
You can specify a root bridge for each MST instance without caring about the
■
device priority. After specifying the current device as the root bridge or a
secondary root bridge, you cannot change the priority of the device.
# Define the current device as the root bridge of MST instance 0.
<Sysname> system-view
[Sysname] stp instance 0 root primary
stp [ instance instance-id ] root secondary
undo stp [ instance instance-id ] root
System view
instance instance-id: MST instance ID, in the range of 0 to 15. MST instance 0
represents the CIST.
Use the
stp root secondary
secondary root bridge of the specified MST instance.
Use the
undo stp root
root bridge of the specified MST instance.
By default, a device is not a secondary root bridge.
Note that:
If you do not provide instance instance-id, your configuration will take effect
■
in the CIST instance only.
You can configure one or more secondary root bridges for each MST instance.
■
When the root bridge of an instance fails or is shut down, the secondary root
bridge can take over the role of the instance of the specified MST instance. If
you specify more than one secondary root bridge, the secondary root bridge
with the lowest Mac address will become the root bridge.
Upon specifying the current device as the root bridge or a secondary root
■
bridge, you cannot change the priority of the device.
# Define the current device as the secondary root bridge of MST instance 0.
<Sysname> system-view
[Sysname] stp instance 0 root secondary
command to specify the current device as a
command to remove the current device as a secondary