Compatible Systems 5.4 Manuale Utente

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Chapter 16 - BGP
If the preferences are the same, the protocol selects the path that has the 
shortest AS path length.
If all paths have the same AS path length, the protocol selects the path 
with the lowest MED.
If the paths have the same MED, the protocol selects the path from the 
BGP peer with the lowest router ID.
v Note:  IP route filters may be used with BGP instead of BGP route maps. 
However, the matching conditions are more limited, and various parameters 
such as community, local preference, and weight cannot be set with IP route 
filters.
The configuration of BGP route maps includes several elements which are 
optional. There can be multiple route names, each uniquely identified by the 
selection of these elements.
BGP route maps are used only by the BGP protocol to filter routes and set 
certain attributes. Route maps are not associated with a particular interface. 
They are applied to the device in the BGP Peer Config Dialog Box.
BGP Route Maps Dialog Box
To access the BGP Route Maps Dialog Box, select BGP/BGP Route Maps 
from the device view.
BGP Route Map Editor Dialog Box Buttons & Controls
The Current Route Map pull-down menu lets you select a route map for 
editing.