3Com Switch 7750 Series
Command Reference Guide – MSTP
Chapter 1 MSTP Configuration Commands
1-25
1.1.23 stp interface port priority
Syntax
stp interface interface-list instance instance-id port priority priority
undo stp interface interface-list instance instance-id port priority
View
System view
Parameter
interface-list
: Ethernet port list. You can specify multiple Ethernet ports by providing this
argument in the form of
interface-list =
{
interface-type interface-number
[
to
interface-type interface-number
] } &<1-10>, where &<1-10> means that you can
provide up to 10 port indexes/port index ranges for this argument.
instance-id
: Spanning tree instance ID ranging from 0 to 16. A value of 0 specifies the
CIST.
priority
: Port priority to be set. This 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 interface port priority
command to set a port priority for the specified
ports in the specified spanning tree instance.
Use the
undo stp interface port priority
command to restore the specified ports to the
default port priority in the specified spanning tree instance.
If you specify the
instance-id
argument to be 0, 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 an 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 results in port roles being re-determined
and may cause state transitions.
Related command:
stp port priority
.
Example
# Set the port priority of Ethernet1/0/3 port (with regard to spanning tree instance 2) to
16.
<3Com> system-view
System View: return to User View with Ctrl+Z.
[3Com] stp interface Ethernet 1/0/3 instance 2 port priority 16
