Configuring The Switching Network Diameter - 3Com 8800 Configuration Manual

3Com Switch 8800 Configuration Guide
discards the configuration BPDU with 0 hops left. This makes it impossible for the
switch beyond the max hops to take part in the spanning tree calculation, thereby
limiting the scale of the MST region.
You can use the following command to configure the max hops in an MST region.
Perform the following configuration in system view.
Table 38-7 Configure the max hops in an MST region
Configure the max hops in an MST region
Restore the default max hops in an MST region
The more the hops in an MST region, the larger the scale of the region. Only the max
hops configured on the region root can limit the scale of MST region. Other switches in
the MST region also apply the configurations on the region root, even if they have been
configured with max hops.
By default, the max hop of an MST is 20.

38.2.6 Configuring the Switching Network Diameter

Any two hosts on the switching network are connected with a specific path carried by a
series of switches. Among these paths, the one passing more switches than all others
is the network diameter, expressed as the number of passed switches.
You can use the following command to configure the diameter of the switching network.
Perform the following configuration in system view.
Table 38-8 Configure the switching network diameter
Configure the switching network diameter
Restore the default switching network diameter
The network diameter is the parameter specifying the network scale. The larger the
diameter is, the lager the scale of the network is.
When a user configures the network diameter on a switch, MSTP automatically
calculates and sets the hello time, forward-delay time and maximum-age time of the
switch to the desirable values.
Setting the network diameter takes effect on CIST only, but has no effect on MSTI.
By default, the network diameter is 7 and the three corresponding timers take the
default values.
Operation
Operation
38-18
Chapter 38 MSTP Region-configuration
Command
stp max-hops hop
undo stp max-hops
Command
stp bridge-diameter bridgenum
undo stp bridge-diameter