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RE: MORE..BGP - Community attribute posted 11/16/2003
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Thank4s Jonathan. I got it.


From: "Jonathan V Hays" <jhays@xxxxxxxx>
To: "'Silvio Nunes'" <silvio_98@xxxxxxxxxxx>, <ccielab@xxxxxxxxxxxxxx>
Subject: RE: MORE..BGP - Community attribute Date: Sun, 16 Nov 2003 09:44:40 -0500


The LOCAL-AS attribute works in exactly the opposite manner: the route
can only be advertised to peers within the same sub-AS within a
confederation. The LOCAL-AS route will not be advertised to other AS's,
even if the other AS is in the same confederation. See the excerpt from
this link, included below.

The communities attribute is an optional, transitive, global attribute
in the numerical range from 1 to 4,294,967,200. Along with Internet
community, there are a few predefined, well-known communities, as

internet-Advertise this route to the Internet community. All routers
belong to it.

no-export-Do not advertise this route to eBGP peers.

no-advertise-Do not advertise this route to any peer (internal or

LOCAL-AS-Do not advertise this route to peers outside the local
autonomous system. This route will not be advertised to other autonomous
systems or sub-autonomous systems when confederations are configured.
Based on

>-----Original Message----- >From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] On >Behalf Of Silvio Nunes >Sent: Sunday, November 16, 2003 9:24 AM >To: ccielab@xxxxxxxxxxxxxx >Subject: MORE..BGP - Community attribute > > >Regarding LOCAL-AS attribute, I4d like to confirm: > >A route with a LOCAL_AS attribute can be advertised to peers in other >subautonomous systems within a confederation, but I4m trying >and it is not >working... the route cannot be advertised to another >subautonomous systems.. > >AS3 (R3)......[ AS10 (subAS5 -R5)----- (subAS5 - R2) ........ >(subAS6 - R6)] >| >| > > >In this example, R2 (in the same subAS) has R6 >(in another >subAS) cannot get the same route: > >(R5) >router bgp 5 >bgp router-id >bgp cluster-id 3368601605 >bgp log-neighbor-changes >bgp confederation identifier 10 >bgp confederation peers 6 >neighbor remote-as 5 >neighbor ebgp-multihop 5 >neighbor update-source Loopback0 >neighbor send-community >neighbor route-map MODCOMMUNITY out >neighbor remote-as 3 >neighbor ebgp-multihop 5 >neighbor update-source Loopback0 > >access-list 33 permit > >route-map MODCOMMUNITY permit 10 >match ip address 33 >set community local-as >! > >_________________________________________________________________ >MSN Hotmail, o maior webmail do Brasil. > >_______________________________________________________________________ >Please help support GroupStudy by purchasing your study materials from: > > >Subscription information may be found at: > > > >

_________________________________________________________________ MSN Hotmail, o maior webmail do Brasil.