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Step Command
Remarks
3.
Configure the hello timer.
•
In STP/RSTP/MSTP mode:
stp timer hello
time
•
In PVST mode:
stp vlan
vlan-list
timer hello
time
Optional.
Use one of the commands.
The default setting is 2
seconds.
4.
Configure the max age
timer.
•
In STP/RSTP/MSTP mode:
stp
timer max-age
time
•
In PVST mode:
stp
vlan
vlan-list
timer max-age
time
Optional.
Use one of the commands.
The default setting is 20
seconds.
Configuring the timeout factor
The timeout factor is a parameter used to decide the timeout time, in the following formula: Timeout time
= timeout factor × 3 × hello time.
After the network topology is stabilized, each non-root-bridge device forwards configuration BPDUs to
the downstream devices at the interval of hello time to determine whether any link is faulty. If a device
does not receive a BPDU from the upstream device within nine times the hello time, it assumes that the
upstream device has failed and starts a new spanning tree calculation process.
Sometimes a device might fail to receive a BPDU from the upstream device because the upstream device
is busy. If a spanning tree calculation occurs, the calculation can fail and also waste 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
device.
stp timer-factor
factor
3 by default.
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.
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 unstable. H3C recommends you to use the default setting.
To configure the maximum rate of a port or a group of ports:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
