Command Manual – MSTP
Quidway S3900 Series Ethernet Switches-Release 1510
Chapter 1 MSTP Configuration Commands
Huawei Technologies Proprietary
1-47
As for the configuration of the three time-related parameters (that is, the Hello time,
Forward delay, and Max age parameters), the following formulas must be met to
prevent network jitter.
2 * (Forward delay – 1 second) >= Max age,
Max age >= 2 * (Hello time + 1 second).
You are recommended to specify the network diameter of the switched network and the
Hello time parameter by using the
stp root primary
or
stp root secondary
command.
After that, the three proper time-related parameters are automatically determined.
Related command:
stp timer forward-delay
,
stp timer hello
, and
stp
bridge-diameter
.
Example
# Set the Max age to 1,000 centiseconds.
<Quidway> system-view
System View: return to User View with Ctrl+Z.
[Quidway] stp timer max-age 1000
1.1.45 stp timer-factor
Syntax
stp timer-factor number
undo
stp timer-factor
View
System view
Parameter
number
: Hello time factor. This argument ranges from 1 to 10 and defaults to 3.
Description
Use the
stp timer-factor
command to set the timeout time of MSTP protocol packets
on a switch in the form of a multiple of the Hello time. For example, with the
number
argument set to 3, the timeout time is three times of the Hello time.
Use the
undo stp timer-factor
command to revert to the default Hello time factor.
A switch regularly sends protocol packets to its neighboring devices at the interval
specified by the Hello time parameter to test the links. Normally, a switch regards its
upstream switch faulty if the former does receive any protocol packets from the latter in
a period three times of the Hello time and then initiates the spanning tree regeneration
process.
