HP E4510-48G, Command Reference Manual

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Description
Use the stp root primary command to configure the current device as the root bridge.
Use the undo stp root command to restore the system default.
By default, a device is not a root bridge in any MSTI.
Note that:
z
There is only one root bridge in effect in an MSTI. If two or more devices have been designated to
be root bridges of the same MSTI, MSTP will select the device with the lowest MAC address as
the root bridge.
z
You can specify a root bridge for each MSTI 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.
Related commands: stp priority , stp root secondary .
Examples
# Specify the current device as the root bridge of MSTI 0.
<Sysname> system-view
[Sysname] stp instance 0 root primary
stp root secondary
Syntax
stp [ instance instance-id ] root secondary
undo stp [ instance instance-id ] root
View
System view
Default Level
2: System level
Parameters
instance instance-id : Configures the device as a secondary root bridge in a particular MSTI. The
minimum value of instance-id is 0, representing the CIST, and the maximum value of instance-id is 32.
Description
Use the stp root secondary command to configure the device as a secondary root bridge.
Use the undo stp root command to restore the system default.
By default, a device is not a secondary root bridge.
Note that:
z
You can configure one or more secondary root bridges for each MSTI. When the root bridge of an
MSTI fails or is shut down, the secondary root bridge can take over the role of the root bridge of
the specified MSTI. However, if you specify a new primary root bridge for the instance then, the
secondary root bridge will not become the root bridge. If you specify more than one secondary
root bridge, the secondary root bridge with the lowest MAC address will become the root bridge.