R3303-HP 6600/HSR6600 Routers Layer 2 - LAN Switching Configuration Guide
66
Ste
p
Command
Remarks
1. Enter system view.
system-view N/A
2. Specify a standard for the
device to use when it
calculates the default path
costs of its ports.
stp pathcost-standard
{ dot1d-1998 | dot1t | legacy }
Optional.
The default standard used by the
device is legacy.
Configuring path costs of ports
When the path cost of a port changes, the system re-calculates the role of the port and initiates a state
transition.
To configure the path cost of ports:
Ste
p
Command
Remarks
1. Enter system view.
system-view N/A
2. Enter interface view or port
group view.
• Enter Ethernet interface view or Layer 2
aggregate interface view:
interface interface-type
interface-number
• Enter port group view:
port-group manual port-group-name
Use one of the commands.
3. Configure the path cost of the
ports.
• In STP/RSTP mode:
stp cost cost
• In MSTP mode:
stp [ instance instance-id ] cost cost
Use one of the commands.
By default, the system
automatically calculates the
path cost of each port.
Configuration example
# In MSTP mode, specify the device to use IEEE 802.1d-1998 to calculate the default path costs of its ports,
and set the path cost of GigabitEthernet 4/0/1 to 200 on MSTI 2.
<Sysname> system-view
[Sysname] stp pathcost-standard dot1d-1998
[Sysname] interface GigabitEthernet 4/0/1
[Sysname-GigabitEthernet4/0/1] stp instance 2 cost 200
Configuring the port priority
The priority of a port is an important factor in determining whether the port can be elected as the root
port of a device. If all other conditions are the same, the port with the highest priority will be elected as
the root port.
On a spanning tree device, a port can have different priorities and play different roles in different
spanning trees, so that data from different VLANs can be propagated along different physical paths to
implement per-VLAN load balancing. You can set port priority values based on your actual network
requirements.
If the port priority changes, the system re-calculates the port role and initiates a state transition.