3com 8807 Reference Guide

C

HAPTER

 13: MSTP C

ONFIGURATION

 C

OMMANDS

Use the stp compliance command to set the format of the packets that the 
current port sends and receives. You can configure the format to legacy, dot1s, 
or auto.

By default, the port sends the packets in the legacy format.

# Set Ethernet2/1/1 to the auto mode.

<SW8800>system-view

 

System View: return to User View with Ctrl+Z.

 

[SW8800] interface Ethernet2/1/1

 

[3Com-Ethernet2/1/1] stp compliance auto 

stp [ instance instance-id ] cost cost

undo stp [ instance instance-id ] cost

Ethernet port view

instance instance-id: Specifies the spanning tree instance ID, ranging from 0 to 
48. The Instance 0 represents CIST.

cost cost: Port path cost. Its range depends on the selected standard of path cost.

Use the stp instance cost command to configure the port path cost on the 
specified MSTI for the current port.

Use the undo stp instance cost command to restore the path cost on the 
specified MSTI.

By default, switch calculates the path costs of a port on different MSTIs.

You may specify the instance-id parameter as 0 to configure CIST path cost of the 
port. The path cost has effect on the port role selection. A port can be configured 
with different path costs on different MSTIs. Thus the traffic from different VLANs 
can run over different physical links, thereby implementing the VLAN-based 
load-balancing. MSTP will recalculate the port role and transit its state, upon the 
port path cost changes.

Related command: stp interface instance cost.

# Set the path cost of Ethernet 2/1/3 on MSTI 2 to 200.

<SW8800>system-view

 

System View: return to User View with Ctrl+Z.

 

[SW8800] interface Ethernet 2/1/3

 

[3Com-Ethernet2/1/3] stp instance 2 cost 200