From: Jerry Hutcheson (jhutches@xxxxxxxxx)
Date: Wed Apr 25 2001 - 10:12:51 GMT-3
Massod,
If the requirement is to not allow your own local AS (100) to be a transit AS,
and you use the community no export would you use a send-community out or in, a
t the ebgp peer (R2)? I have heard it both ways it seems to me that it should b
e a send community in.
thanks,
jerry
and At 09:04 AM 4/25/2001 +1000, Masood Malik wrote:
>RE: BGP filtering without IP address FiltersHi,
>
>The main difference between no-export and no-advertise is as follows.
>
>When no-export community is set in an AS for a route it will be passed through
>all the routers in the same AS (IBGP) and also to the next neighbour AS
>(EBGP). However, this neighbour AS will not pass it to its up stream AS.
>
>Thus no-exports cannot work in the same AS.
>
>When you set no-advertise community on a router in any AS, the route will not
>be advertised to any neighbour AS whether it is same (IBGP) or different
>(EBGP).
>
>e.g. if you have following scenario
>
>R1 (AS100)---R2 (AS100)----R3(AS200)------R4(AS300)
>
>If no-export community is set on a route entering R1. You will see the route
>in R2 and R3 but not in R4.
>
>If no-advertise community is set on a route entering R1. The route will be
>missing in R2, R3 or R4.
>
>Note: In order for all this to work correctly, ensure setting send-community
>to the neighour AS peers in each router.
>
>regards
>Masood
> ----- Original Message -----
> From: Chia Kim Seng, Consultant, SCSNW-Sales
> To: 'Masood Malik' ; Vladimir Shchutski ; Dean, Justin ;
>ccielab@groupstudy.com
> Sent: Tuesday, April 24, 2001 11:46 AM
> Subject: RE: BGP filtering without IP address Filters
>
>
> Can I use no-export community instead?
>
> Regards
> Chia Kim Seng
>
> SCS Networks Pte Ltd
> 7 Bedok South Road
> Singapore 469272
> Tel : 065-2403164
> Fax: 065-2403110
>
>
>
> -----Original Message-----
> From: Masood Malik [mailto:malikm24@hotmail.com]
> Sent: Tuesday, April 24, 2001 6:21 AM
> To: Vladimir Shchutski; Dean, Justin; ccielab@groupstudy.com
> Subject: Re: BGP filtering without IP address Filters
>
>
>
> set no-advertise community for 1.1.1.1 on R2
>
> regards
> Masood
>
> ----- Original Message -----
> From: "Vladimir Shchutski" <vshchutski@yahoo.com>
> To: "Dean, Justin" <Justin.Dean@nrtinc.com>; <ccielab@groupstudy.com>
> Sent: Tuesday, April 24, 2001 7:42 AM
> Subject: Re: BGP filtering without IP address Filters
>
>
>
> > try community names.
> >
> > Regards,
> > Vladimir.
> >
> > --- "Dean, Justin" <Justin.Dean@nrtinc.com> wrote:
> > > I am trying to have R2 filter the 1.1.1.1 from being
> > > advertised to R3. The
> > > requirement is that you cannot filter by ip address.
> > > I thought I could tag
> > > it with a route-map at R1 then match tag at R2 and
> > > dump it, but I get an
> > > error trying to put the set tag in the route-map and
> > > apply it to the
> > > neighbor outbound. I also tried to prepend as's, but
> > > since R1 and R2 are in
> > > same as the route shows as "i". Any Ideas? justin
> > >
> > >
> > > 1.1.1.1-------R1----IBGP---R2---EBGP---R3----
> > > **Please
> > > read:http://www.groupstudy.com/list/posting.html
> > >
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