Configuring Port Priority - 3Com 4500 Configuration Manual

[Sysname] undo stp interface Ethernet 1/0/1 instance 1 cost
[Sysname] stp pathcost-standard dot1d-1998
2) Perform this configuration in Ethernet port view
<Sysname> system-view
[Sysname] interface Ethernet 1/0/1
[Sysname-Ethernet1/0/1] undo stp instance 1 cost
[Sysname-Ethernet1/0/1] quit
[Sysname] stp pathcost-standard dot1d-1998

Configuring Port Priority

Port priority is an important criterion on determining the root port. In the same condition, the port with the
smallest port priority value becomes the root port.
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 that
VLAN-based load balancing can be implemented.
You can configure port priority in one of the following two ways.
Configure port priority in system view
Follow these steps to configure port priority in system view:
To do...
Enter system view
Configure port priority for
specified ports
Configure port priority in Ethernet port view
Follow these steps to configure port priority in Ethernet port view:
To do...
Enter system view
Enter Ethernet port view
Configure port priority for the
port
Changing port priority of a port may change the role of the port and put the port into state transition.
A smaller port priority value indicates a higher possibility for the port to become the root port. If all the
ports of a switch have the same port priority value, the port priorities are determined by the port indexes.
Changing the priority of a port will cause spanning tree recalculation.
You can configure port priorities according to actual networking requirements.
Configuration example
# Configure the port priority of Ethernet 1/0/1 in MSTI 1 to be 16.
Use the command...
system-view
stp interface interface-list
instance instance-id port
priority priority
Use the command...
system-view
interface interface-type
interface-number
stp [ instance instance-id ]
port priority priority
1-32
Remarks
—
Required
The default port priority is 128.
Remarks
—
—
Required.
The default port priority is 128.