Cabletron Systems NB30 manual Configuring Spanning Tree, Topology, Changing Bridge Priority

NB-30 Bridging

Topology

This indicates how many times the bridgeÕs Topology Change ßag has been changed since the NB-30 was last powered-up or initialized. The Topology Change ßag increments each time a bridge enters or leaves the network, or when the Root Bridge ID changes. The Þeld also indicates the date and time at which the topology last changed.

Configuring Spanning Tree

The Bridge Spanning Tree window allows you to update the following parameters for your NB-30 bridge. When you have Þnished making changes to the following individual parameters, you must click on Set at the bottom of the Spanning Tree window to write the changes to the device.

NOTE

Any values you set at the bridge will cause a Topology Change ßag to be issued in the next ConÞguration BPDUs it transmits. This will cause the bridged network to immediately recalculate Spanning Tree and change topology accordingly.

Changing Bridge Priority

To change the part of the bridge address that contains the identiÞer used in the Spanning Tree Algorithm for priority comparisons:

1.Highlight the Bridge Priority field.

2.Enter the new identifier, in hexadecimal format; the allowed range is 0-FFFF hexadecimal.

3.Click on Set.

The selected Bridge Priority will be applied to the bridge (a lower number indicates a higher priority in the root selection process).

Changing the Spanning Tree Algorithm Protocol Type

To change the type of protocol used in Spanning Tree:

1.Click the mouse on the appropriate option button: IEEE 802.1, DEC, or None.

2.Click on Set.

The selected Spanning Tree Algorithm protocol type will be applied to the bridge. If you selected None, the Spanning Tree Algorithm will be disabled (if it already was enabled). If STA Protocol Type was changed from None to IEEE 802.1 or DEC, you must restart the bridge for the newly selected STA protocol to be applied.

3-22 Bridge Spanning Tree