Huawei Quidway S3900 Series User Manual

Operation Manual – MSTP
Quidway S3900 Series Ethernet Switches-Release 1510 Chapter 1 MSTP Configuration
Huawei Technologies Proprietary
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when the new spanning trees are generated, loops may occur if the new root ports and
designated ports begin to forward packets immediately.
This can be avoided by adopting a state transition mechanism. With this mechanism,
newly selected root ports and designated ports undergo an intermediate state before
they begin to forward packets. That is, it costs these ports a period (specified by the
Forward delay parameter) for them to turn to the forwarding state. The period ensures
that the newly generated configuration BPDUs to propagate across the entire network.
z The Hello time parameter is for link testing.
A switch regularly sends hello packets to other switches in the interval specified by the
Hello time parameter to test the links.
z The Max age parameter is used to judge whether or not a configuration BPDU is
obsolete. Obsolete configuration BPDUs will be discarded.
I. Configuration procedure
Table 1-11 Configure MSTP time-related parameters
Operation Command Description
Enter system view
system-view
—
Configure the Forward
delay parameter
stp timer forward-delay
centiseconds
Required
The Forward delay
parameter defaults to 1,500
centiseconds (15 seconds).
Configure the Hello
time parameter
stp timer hello
centiseconds
Required
The Hello time parameter
defaults to 200
centiseconds (2 seconds).
Configure the Max age
parameter
stp timer max-age
centiseconds
Required
The Max age parameter
defaults to 2,000
centiseconds (20 seconds).
All switches in a switched network adopt the three time-related parameters configured
on the CIST root bridge.

Huawei Quidway S3900 Series Specifications

General

Brand	Huawei
Model	Quidway S3900 Series
Category	Switch
Language	English