BGP Filtering

[John McNumara]

Wendell Odom's CCNP ROUTE 642-902 book states that "BGP configuration does not allow filtering of all inbound or outbound updates.  Instead, the BGP filtering configuration enables filters per neighbor (using a neighbor command)..."  The text goes on to demonstrate the neighbor distribute-list, neighbor prefix-list, neighbor filter-list and neighbor route-map BGP subcommands. 

Is the text omitting the distribute-list BGP subcommand on purpose?  Granted, it cannot match details that are in route-maps, but I wouldn't consider writing the command off entirely.  I want to go into the CCNP ROUTE, facing the question "Can BGP filtering be applied to all outbound or inbound updates?" and know the answer. 

Any clarification is appreciated

Thanks

[antonio.guirado]

Hello John,

yes, you can do it. I just test it and works. You can use distribute-list to filter inbound updates or filter network

to be announced.

http://www.cisco.com/en/US/docs/ios/12_2/iproute/command/reference/1rfbgp1.html#wp1257989

Regards.

[paul driver]

Hello John

You can also so use outbound route filtering (orf)
In which you tell your neighbouring bgp peer what routes you want them to send you

Both routers need to able to support this feature and it does require your neighbouring router to set orf on on their side also to receive your orf filters but it can cut down on the amount of routes your router receives from them and if this is an ISP router that may be a significant amount.


http://blog.ine.com/2008/05/05/understanding-bgp-outbound-route-filtering-bgp-orf/

Res
Paul
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