Cabletron Systems 9A128-01 Manual De Usuario
Bridging
5-20
Bridge Spanning Tree
Changing Max Age Time
If the selected module is the Root Bridge or attempting to become the Root, and
you want to change the maximum time that bridge protocol information will be
kept before it is discarded:
you want to change the maximum time that bridge protocol information will be
kept before it is discarded:
1.
Highlight the Max Age field, and type in a new value.
2.
Click on Set.
The IEEE 802.1d specification recommends that Max Age = 20 seconds; the
allowable range is 6 to 40 seconds.
allowable range is 6 to 40 seconds.
Changing Forwarding Delay Time
If the selected module is the Root Bridge or attempting to become the Root, and
you want to change the time period the bridge will spend in the Listening state
(e.g. either listening to BPDU activity on the network while moving from the
Blocking to the Learning state or in the Learning state while the bridge is moving
from the Listening to the Forwarding state):
you want to change the time period the bridge will spend in the Listening state
(e.g. either listening to BPDU activity on the network while moving from the
Blocking to the Learning state or in the Learning state while the bridge is moving
from the Listening to the Forwarding state):
1.
Highlight the Forwarding Delay field, and type in a new value.
2.
Click on Set.
The IEEE 802.1d specification recommends that Forward Delay = 15 seconds; the
allowable range is 4 to 30 seconds.
allowable range is 4 to 30 seconds.
Changing Port Priority
To change the part of the Port Priority used in priority comparisons:
1.
If necessary, select the desired port by clicking the mouse to highlight the port
in the lower right quadrant of the window. The lower left quadrant of the
window will now allow you to edit parameters for the selected port.
in the lower right quadrant of the window. The lower left quadrant of the
window will now allow you to edit parameters for the selected port.
2.
Highlight the port Priority field, and enter the new priority identifier. Only valid
hexadecimal numbers (0 to FF) are allowed in this field. The default is 80
hexadecimal.
hexadecimal numbers (0 to FF) are allowed in this field. The default is 80
hexadecimal.
3.
Click on Set. The new port priority will be saved.
NOTE
To ensure proper operation of the Spanning Tree Algorithm, the IEEE 802.1d specification
recommends that you always observe the following relationship between Forwarding
Delay and Max Age:
recommends that you always observe the following relationship between Forwarding
Delay and Max Age:
2 x (Forwarding Delay - 1.0) > Max Age