3Com 4800G Series, Configuration Manual

Page: 218 / 1246

218 C
HAPTER
23: MSTP C
ONFIGURATION
n
A larger maximum hops setting means a larger size of the MST region. Only the
maximum hops configured on the regional root bridge can restrict the size of the
MST region.
Configuration example
# Set the maximum hops of the MST region to 30.
<Sysname> system-view
[Sysname] stp max-hops 30
Configuring the
Network Diameter of a
Switched Network
Any two stations in a switched network are interconnected through specific paths,
which are composed of a series of devices. Represented by the number of devices
on a path, the network diameter is the path that comprises more devices than any
other among these paths.
Configuration procedure
Follow these steps to configure the network diameter of the switched network:
n
■
Network diameter is a parameter that indicates network size. A bigger network
diameter represents a larger network size.
■
Based on the network diameter you configured, MSTP automatically sets an
optimal hello time, forward delay, and max age for the device.
■
The configured network diameter is effective for the CIST only, and not for
MSTIs.
Configuration example
# Set the network diameter of the switched network to 6.
<Sysname> system-view
[Sysname] stp bridge-diameter 6
Configuring Timers of
MSTP
MSTP involves three timers: forward delay, hello time and max age. You can
configure these three parameters for MSTP to calculate spanning trees.
Configuration procedure
Follow these steps to configure the timers of MSTP:
To do… Use the command… Remarks
Enter system view system-view -
Configure the network diameter of the
switched network stp bridge-diameter bridge-number Optional
7 by default
To do… Use the command… Remarks
Enter system view system-view -
Configure the forward delay
timer stp timer forward-delay
centi-seconds
Optional
1,500 centiseconds (15
seconds) by default
Configure the hello time timer stp timer hello centi-seconds Optional
200 centiseconds (2 seconds)
by default