3com 8807 Guia De Referência

Use the stp bridge-diameter command to configure the switching network 
diameter. Use the undo stp bridge-diameter command to restore the default 
network diameter.

The definition of network diameter: Maximum count of switches between the 
farthest communication ends.

The stp bridge-diameter command configures the switching network diameter 
and determines the three time parameters of MSTP accordingly. This configuration 
takes effect on CIST only but makes no sense for MSTI.

The spanning tree convergence can be speeded up, when Hello Time, Forward 
Delay, and Max Age are well configured. These parameters are related to the 
network scale.

You can configure the network scale to get the time parameters. When users 
configure the bridge-diameter parameter of the switch, MSTP will automatically 
set Hello Time, Forward Delay, and Max Age to moderate values. When 
bridge-diameter defaults to 7, the time parameters also take their respective 
default values.

Related command: stp timer forward-delay, stp timer hello, stp timer 
max-age.

n 

# Set the diameter of the switching network to 5.

<SW8800>system-view

 

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

 

[SW8800] stp bridge-diameter 5 

stp compliance { legacy | dot1s | auto }

Ethernet port view

legacy: Indicates that the port sends and receives private MSTP packets.

dot1s: Indicates that the port sends and receives standard MSTP packets.

auto: Indicates the port has the auto-sensing function. The port can automatically 
adjust the format of the packet to be sent based on the format of the received 
packet.