Cabletron Systems SPECTRUM, Руководство пользователя

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The Spanning Tree Port Parameters Window 6-25
Using the 7C0x SmartSwitch Bridge View
The Spanning Tree Port Parameters Window
The Spanning Tree Algorithm ensures that only a single bridge path exists
between any two end stations in a network designed with multiple bridges
placed in parallel; it also ensures that on any given bridge, only one port path
exists between the bridge and any one network segment. In the Spanning Tree
Port Table you can view and edit the Spanning Tree values for individual ports;
the Spanning Tree Port parameters affect a port’s participation in the Spanning
Tree.
To open the Spanning Tree Port Table window:
1. Display the Device menu by clicking on the Front Panel button.
2. Drag down to Spanning Tree to open the Spanning Tree Protocol window.
3. In the Spanning Tree Protocol window, click on the Spanning Tree Port Table
button.
or
1. In the Bridge Traffic View, click mouse button 3 on a port to display the Port
menu and drag down to Spanning Tree.
The scroll list at the top of the window lists each bridge port available on the
device and its current port priority. Below the Port List, the window includes the
following:
Priority (Port)
If two or more ports on the same bridge are connected to the same network
segment, each port will receive the same device-level values for Root ID, Root
Cost, and Bridge ID in Configuration BPDUs. In this case, the BPDU’s port-level
information—the transmitting port’s identifier and its manageable Priority
component— is used to determine which port on this bridge will be the
Designated Port for that segment. A lower number indicates a higher priority; the
default is 80. The allowable range is 0 to FF.
Path Cost
The portion of the total path cost associated with this port. Lowering a port’s Path
Cost makes a port more competitive in the selection of the Designated Port. The
default value is 100 for Cabletron bridges. The allowable range is from 1 to 65535.
NOTE
Setting Spanning Tree Port Parameters only affects port selection on a particular bridge;
settings do not affect the 7C0x SmartSwitch’s device-level priority in the network’s
Spanning Tree.