3Com Switch 7750 Series
Command Reference Guide – MSTP Chapter 1 MSTP Configuration Commands
1-36
port priority priority: Sets the port priority. The priority argument ranges from 0 to 240
and must be a multiple of 16 (such as 0, 16, and 32). The default port priority of a port in
any spanning tree instance is 128.
Description
Use the stp port priority command to set the port priority of the current port in the
specified spanning tree instance.
Use the undo stp port priority command to restore the current port to the default port
priority in the specified spanning tree instance.
If you specify the instance-id argument to be 0 or do not specify the argument, these
two commands apply to the port priorities on the CIST. The role a port plays in a
spanning tree instance is determined by the port priority in the instance. A port on a
MSTP-enabled switch can have different port priorities and play different roles in
different MSTIs. This enables packets of different VLANs to be forwarded along
different physical paths, so as to achieve load balancing by VLANs. Changing port
priorities result in port roles being re-determined and may cause state transitions.
Related command: stp interface port priority.
Example
# Set the port priority of Ethernet1/0/3 port in spanning tree instance 2 to 16.
<3Com> system-view
System View: return to User View with Ctrl+Z.
[3Com] interface Ethernet1/0/3
[3Com-Ethernet1/0/3] stp instance 2 port priority 16
1.1.34 stp priority Syntax
stp [ instance instance-id ] priority priority
undo stp [ instance instance-id ] priority
View
System view
Parameter
instance-id: Spanning tree instance ID ranging from 0 to 16. A value of 0 specifies the
CIST.
priority: Switch priority to be set. This argument ranges from 0 to 61,440 and must be a
multiple of 4,096 (such as 0, 4,096, and 8,192). There are totally 16 available switch
priorities.