108
Link speed
Port type
Path cost
IEEE
802.1d-1998
IEEE 802.1t
Private
standard
containing three Selected
ports
Aggregate interface
containing four Selected
ports
125 1
100 Gbps
Single port
1
200 1
Aggregate interface
containing two Selected
ports
100 1
Aggregate interface
containing three Selected
ports
66 1
Aggregate interface
containing four Selected
ports
50 1
Configuring path costs of ports
When the path cost of a port changes, the system recalculates the role of the port and initiates a
state transition.
To configure the path cost 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 path cost of
the ports.
•
In
STP/RSTP
mode:
stp cost cost-value
•
In
PVST
mode:
stp
vlan
vlan-id-list
cost cost-value
•
In
MSTP
mode:
stp
[
instance instance-list
]
cost
cost-value
By default, the system
automatically calculates
the path cost of each port.
Configuration example
# In MSTP 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 200 on MSTI 2.
<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