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Sometimes a router may fail to receive a BPDU from the upstream router because the upstream router is
busy. If a spanning tree calculation occurs, the calculation can fail and also waste the network resources.
In a stable network, you can prevent undesired spanning tree calculations by setting the timeout factor to
5, 6, or 7.
To configure the timeout factor:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Configure the timeout factor of the router.
stp timer-factor
factor
The default setting is 3.
Configuring the maximum port rate
The maximum rate of a port refers to the maximum number of BPDUs the port can send within each hello
time. The maximum rate of a port is related to the physical status of the port and the network structure.
To configure the maximum rate of a port or a group of ports:
Step Command Remarks
1.
Enter system view.
system-view
N/A
2.
Enter interface view or port
group view.
•
Enter Ethernet interface view or Layer
2 aggregate interface view:
interface
interface-type
interface-number
•
Enter port group view:
port-group manual
port-group-name
Use one of the commands.
3.
Configure the maximum rate
of the ports.
stp transmit-limit
limit
The default setting is 10.
NOTE:
The higher the maximum port rate is, the more BPDUs will be sent within each hello time, and the more
system resources will be used. By setting an appropriate maximum port rate, you can limit the rate at
which the port sends BPDUs and prevent spanning tree protocols from using excessive network resources
when the network becomes instable. H3C recommends you to use the default setting.
Configuring edge ports
If a port directly connects to a user terminal rather than another router or a shared LAN segment, this port
is regarded as an edge port. When a network topology change occurs, an edge port will not cause a
temporary loop. Because a router does not know whether a port is directly connected to a terminal, you
need to manually configure the port to be an edge port. After that, this port can transition rapidly from
the blocked state to the forwarding state without delay.
To specify a port or a group of ports as edge port or ports:
Step Command Remarks
1.
Enter system view.
system-view
N/A
