3Com Switch 4500 26-Port, Руководство по настройке

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180 C
HAPTER
10: RSTP C
ONFIGURATION
that if the Forward Delay is configured too short, occasional path redundancy may
occur. If the Forward Delay is configured too long, restoring the network
connection may take a long time. It is recommended to use the default setting.
By default, the bridge Forward Delay is 15 seconds.
Set Hello Time of the
Specified Bridge
A bridge transmits hello packet regularly to the adjacent bridges to check if there
is link failure.
You can use the following command to set the Hello Time of a specified bridge.
Perform the following configurations in System View.
Table 177 Set Hello Time of the Specified Bridge
An appropriate Hello Time can ensure that the bridge can detect certain link
failures in the network in a timely manner. It is strongly recommended that default
value of 2 seconds is retained.
By default, the Hello Time of the bridge is 2 seconds.
Set Max Age of the
Specified Bridge
Max Age is a parameter to judge whether the configuration BPDU is “timeout”.
Users can configure it according to the actual network situation.
You can use the following command to set Max Age of a specified bridge.
Perform the following configuration in System View.
Table 178 Set Max Age of the Specified Bridge
If the Max Age is too short, it will result in frequent calculation of spanning tree or
misjudge the network congestion as a link fault. On the other hand, too long Max
Age may make the bridge unable to find link failure in time and weaken the
network auto-sensing ability. It is recommended to use the default setting.
By default, the bridge Max Age is 20 seconds.
Set Timeout Factor of
the Bridge
A bridge transmits hello packet regularly to the adjacent bridges to check if there
is link failure. Generally, if the Switch does not receive the RSTP packets from the
upstream Switch for 3 occurrences of hello time, the Switch will decide the
upstream Switch is dead and will recalculate the topology of the network. Then in
a steady network, the recalculation may be caused when the upstream Switch is
busy. In this case, you can redefine the timeout interval to a longer time by
defining the multiple value of hello time.
Operation Command
Set Hello Time of the specified bridge
stp timer hello centiseconds
Restore the default Hello Time of the specified
bridge
undo stp timer hello
Operation Command
Set Max Age of the specified bridge
stp timer max-age
centiseconds
Restore the default Max Age of the specified bridge
undo stp timer max-age