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[Sysname-HundredGigE1/0/3] stp instance 2 cost 200
# In PVST mode, perform the following tasks:
•
Configure the device to calculate the default path costs of its ports by using IEEE 802.1d-1998.
•
Set the path cost of HundredGigE 1/0/3 to 2000 on VLAN 20 through VLAN 30.
<Sysname> system-view
[Sysname] stp pathcost-standard dot1d-1998
Cost of every port will be reset and automatically re-calculated after you change the
current pathcost standard. Continue?[Y/N]:y
Cost of every port has been re-calculated
[Sysname] interface hundredgige 1/0/3
[Sysname-HundredGigE1/0/3] stp vlan 20 to 30 cost 2000
Configuring the port priority
The priority of a port is a factor that determines 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 is elected as the root
port.
On a spanning tree device, a port can have different priorities and play different roles in different
spanning trees. As a result, data of different VLANs can be propagated along different physical paths,
implementing per-VLAN load balancing. You can set port priority values based on the actual
networking requirements.
When the priority of a port changes, the system recalculates the port role and initiates a state
transition.
To configure the priority of a port:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter Layer 2 Ethernet
interface or Layer 2
aggregate interface view.
interface interface-type interface-number
N/A
3.
Configure the port priority.
•
In STP/RSTP mode:
stp port priority priority
•
In PVST mode:
stp
vlan
vlan-id-list
port priority
priority
•
In MSTP mode:
stp
[
instance instance-list
]
port
priority priority
The default setting is 128
for all ports.
Configuring the port link type
A point-to-point link directly connects two devices. If two root ports or designated ports are connected
over a point-to-point link, they can rapidly transit to the forwarding state after a proposal-agreement
handshake process.
Configuration restrictions and guidelines
When you configure the port link type, follow these restrictions and guidelines: