H3C SOHO IE4300, Command Reference Manual

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Usage guidelines
In the CIST of an MSTP network, the device determines whether a configuration BPDU received on
a port has expired based on the max age timer. If the configuration BPDU has expired, a new
spanning tree calculation process starts. The max age timer takes effect only on the CIST (or MSTI
0).
As a best practice, do not set the max age timer with this command. Instead, you can specify the
network diameter of the switched network by using the
stp bridge-diameter
command. This
command makes the spanning tree protocols automatically calculate the optimal settings for the max
age timer. If the network diameter uses the default value, the max age timer also uses the default
value.
Examples
# In MSTP mode, set the max age timer to 1000 centiseconds.
<Sysname> system-view
[Sysname] stp timer max-age 1000
# In PVST mode, set the max age timer for VLAN 2 to 1000 centiseconds.
<Sysname> system-view
[Sysname] stp vlan 2 timer max-age 1000
Related commands
stp bridge-diameter
stp timer forward-delay
stp timer hello
stp timer-factor
Use stp timer-factor to configure the timeout period by setting the timeout factor.
Timeout period = timeout factor × 3 × hello time.
Use undo stp timer-factor to restore the default.
Syntax
stp timer-factor factor
undo stp timer-factor
Default
The timeout factor of the device is set to 3.
Views
System view
Predefined user roles
network-admin
Parameters
factor
: Specifies the timeout factor in the range of 1 to 20.
Usage guidelines
In a stable network, each non-root-bridge forwards configuration BPDUs to surrounding devices at
the interval of hello time to determine whether any link fails. If a device does not receive a BPDU from
the upstream device within nine times of the hello time, it assumes that the upstream device has
failed. Then it will start a new spanning tree calculation process.