User's Manual

Table Of Contents
233
Users Manual of CS-6306R
Command Purpose
spanning-tree mstpinstance-idroot primary
[ diameternet-diameter
[ hello-timeseconds ] ]
Sets the switch to the root in the designated
spanning tree instance.
instance-id represents the number of the spanning
tree instance, ranging from 0 to 15.
net-diameter represents the network diameter,
which is an optional parameter. It is effective when
instance-id is 0. It ranges from 2 to 7.
seconds represents the unit of the hello time,
ranging from 1 to 10.
no spanning-tree mstpinstance-idroot
Cancels the root configuration of the switch in the
spanning tree.
instance-id means the number of the spanning tree
instance, ranging from 0 to 15.
Run the following command to check the MSTP message:
Command Purpose
show spanning-tree mstp
[ instanceinstance-id ]
Checks the MSTP message.
19.2.3.5 Configuring Secondary Root
After the network root is configured, you can run spanning-tree mstpinstance-idroot secondary to set one
or multiple switches to the secondary roots or the backup roots. If the root does not function for certain
reasons, the secondary roots will become the network root.
Different from the primary root configuration, after the command to configure the primary root is run, MSTP
sets the spanning tree priority of the switch to 28672. In the case that the priority value of other switches is the
default value 32768, the current switch can be the secondary root.
When configuring the secondary root, you can run the subcommands diameter and hello-time to update the
STP time parameters. When the secondary root becomes the primary root and starts working, all these
parameters starts functioning.
Run the following command to set the switch to the secondary root of the network: