3Com 4500 PWR 26-Port Configuration Manual page 255

Configuring the Timeout Time Factor
When the network topology is stable, a non-root-bridge switch regularly forwards BPDUs received from
the root bridge to its neighboring devices at the interval specified by the hello time parameter to check
for link failures. Normally, a switch regards its upstream switch faulty if the former does not receive any
BPDU from the latter in a period three times of the hello time and then initiates the spanning tree
recalculation process.
Spanning trees may be recalculated even in a steady network if an upstream switch continues to be
busy. You can configure the timeout time factor to a larger number to avoid such cases. Normally, the
timeout time can be four or more times of the hello time. For a steady network, the timeout time can be
five to seven times of the hello time.
Configuration procedure
Follow these steps to configure the timeout time factor:
To do...
Enter system view
Configure the timeout time
factor for the switch
For a steady network, the timeout time can be five to seven times of the hello time.
Configuration example
# Configure the timeout time factor to be 6.
<Sysname> system-view
[Sysname] stp timer-factor 6
Configuring the Maximum Transmitting Rate on the Current Port
The maximum transmitting rate of a port specifies the maximum number of configuration BPDUs a port
can transmit in a period specified by the hello time parameter. It depends on the physical state of the
port and network structure. You can configure this parameter according to the network.
Configure the maximum transmitting rate for specified ports in system view
Follow these steps to configure the maximum transmitting rate for specified ports in system view:
To do...
Enter system view
Configure the maximum
transmitting rate for specified
ports
Configure the maximum transmitting rate in Ethernet port view
Follow these steps to configure the maximum transmitting rate in Ethernet port view:
Use the command...
system-view
stp timer-factor number
Use the command...
system-view
stp interface interface-list
transmit-limit packetnum
20-25
Remarks
—
Required
The timeout time factor defaults
to 3.
Remarks
—
Required
The maximum transmitting rate
of all Ethernet ports on a switch
defaults to 10.