HP MSR2000/3000/4000 Router Series Layer 2 - LAN Switching Configuration Guide

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Configuring path costs of ports
Path cost is a parameter related to the rate of a port. On a spanning tree device, a port can have different
path costs in different MSTIs. Setting appropriate path costs allows VLAN traffic flows to be forwarded
along different physical links, achieving VLAN-based load balancing.
You can have the device automatically calculate the default path cost, or you can configure the path cost
for ports.
Specifying a standard for the device to use when it calculates
the default path cost
CAUTION:
If you change the standard that the device uses to calculate the default path costs, you restore the path
costs to the default.
You can specify a standard for the device to use in automatic calculation for the default path cost. The
device supports the following standards:
• dot1d-1998—The device calculates the default path cost for ports based on IEEE 802.1d-1998.
• dot1t—The device calculates the default path cost for ports based on IEEE 802.1t.
• legacy—The device calculates the default path cost for ports based on a private standard.
To specify a standard for the device to use when it calculates the default path cost:
Step 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 }
By default, legacy applies.
Table 5 Mappings between the link speed and the path cost
Link speed Port type
Path
cost
IEEE
802.1d-1998
IEEE 802.1t Private standard
0 N/A 65535 200000000 200000
10 Mbps Single port 100 2000000 2000
100 Mbps Single port 19 200000 200
1000 Mbps Single port 4 20000 20
10 Gbps Single port 2 2000 2