3Com 5500 SI - Switch - Stackable, Configuration Manual

Page: 181 / 686

Leaf Node Configuration 181
Configuring MSTP
Operation Mode
Refer to “Configuring MSTP Operation Mode”.
Configuring the Timeout
Time Factor
Refer to “Configuring the Timeout Time Factor”.
Configuring the
Maximum Transmission
Speed of a Port
Refer to “Configuring the Maximum Transmission Speed of a Port”.
Setting a Port as an Edge
Port
Refer to “Setting a Port as an Edge Port”.
Configuring the Path
Cost of a Port
The path cost of a port is related with the speed of the connected link. A port of an
MSTP-enabled switch can have different path costs for different spanning tree
instances. By configuring proper path costs, you can enable flows of different VLANs
to travel along different physical links to implement VLAN-based load balancing.
Path cost can be configured manually or be determined by the switch.
Specifying the standard for calculating path costs of ports
Currently, the following standards are available for calculating path costs of ports on a
switch:
■
dot1d-1998 : Adopts the IEEE 802.1D-1998 standard to calculate the default path
costs of ports.
■
dot1t : Adopts the IEEE 802.1t standard to calculate the default path costs of
ports.
■
legacy : Adopts the standard defined by 3Com-3Com Technology Co., Ltd to
calculate the default path costs of ports.
Table 160 Specify the standard for calculating path costs
Operation Command Description
Enter system view system-view -
Specify the standard for
calculating the default path
costs of links connecting to
the switch stp pathcost-standard
{
dot1d-1998 | dot1t | legacy
}
Optional
By default, the IEEE 802.1t
standard is used to calculate the
default path costs of ports.
Table 161 Transmission speeds and the corresponding path costs
Transmission
speed Operation mode
(half-/full-duplex)
802.1D-1998 IEEE 802.1t
3Com-3Com
standard
0 — 65,535 200,000,000 200,000
10 Mbps Half-Duplex
Full-Duplex
Aggregated Link 2 Ports
Aggregated Link 3 Ports
Aggregated Link 4 Ports
100
99
95
95
95
2,000,000
1,999,999
1,000,000
666,666
500,000
2,000
2,000
1,800
1,600
1,400