From: Nelson Salvatorelli (nsalvato@xxxxxxxxx)
Date: Sun Mar 24 2002 - 19:01:06 GMT-3
I think the original message from Carl specified that configuring the
following step by step, line by line:
router bgp 65535
neighbor w.x.y.z remote-as AS1
neighbor w.x.y.z route-map <name1> out
neighbot w.x.y.z route-map <name2> out
...
And the result when doing 'wr t' was:
router bgp 65535
neighbor w.x.y.z remote-as AS1
neighbot w.x.y.z route-map <name2> out
...
This is absolutely correct! The IOS implementation only allows one
route-map statement on each way per neighbor, i.e. incoming and
outgoing. So that's why the latest config line overrides the previous
one... ;-)
You have to carefully design your filtering strategy to be sure you
cover all the match/set statements with one route-map definition for
incoming and for outgoing.
Follow Tim's email advice in terms of the matching sequence of
route-maps (i.e. permit 10 is checked, then permit 20, and so on...)
Hope it clarifies,
Cheers,
-nelson
> -----Original Message-----
> From: Ouellette, Tim [mailto:tim.ouellette@eds.com]
> Sent: 24 March 2002 06:15
> To: Ouellette, Tim; 'Ahmed Mamoor Amimi'; 'Carl Phelan'
> Cc: 'ccielab@groupstudy.com'
> Subject: RE: BGP - Transit Area and now Route-Maps
>
>
> Just as I though, it looks as if once I match is met, that's
> it. If no match is met then it continues on until there is
> no more (implicit deny)
>
> excerpt from the link
>
> When BGP applies MYMAP to routing updates, it applies the
> lowest instance first (in this case, instance 10). If the
> first set of conditions is not met, the second instance is
> applied, and so on, until either a set of conditions has been
> met, or there are no more sets of conditions to apply.
>
>
> http://www.cisco.com/univercd/cc/td/doc/cisintwk/ics/icsbgp4.h
> tm#xtocid20439
> 8
>
> -----Original Message-----
> From: Ouellette, Tim
> Sent: Sunday, March 24, 2002 1:10 AM
> To: 'Ahmed Mamoor Amimi'; Carl Phelan; Ouellette, Tim
> Cc: ccielab@groupstudy.com
> Subject: RE: BGP - Transit Area and now Route-Maps
>
>
> Ahmed,
>
> I believe that you need to watch the order. Obviously in an
> ACL once you match a list than that action is performed
> (deny/permit) but I believe that a route-map would be the
> same. So in your example, all routes incoming will match
> your sequence #10, since you have no match statement means
> match all, then you'll set the no-export and that's it. I
> don't think it'll go onto the next instance. I'll have to
> read up but i think that's the way it works. I think what you
> might want to do is like this.
>
> route-map comm&metric permit 10
> match ip add x
> set community no-export
> set metric 200
>
> route-map comm&metric permit 20
> set metric 200
>
> router bgp 99
> neighbor x.x.x.x route-map comm&metric out
>
> -----Original Message-----
> From: Ahmed Mamoor Amimi [mailto:mamoor@ieee.org]
> Sent: Sunday, March 24, 2002 12:59 AM
> To: Carl Phelan; 'Ouellette, Tim'
> Cc: ccielab@groupstudy.com
> Subject: Re: BGP - Transit Area and now Route-Maps
>
>
> Can u try this one.
> This will put the community "no-export" to every route
>
> R1
> router-map comm&metric-set permit 10
> set community no-export
>
> router-map comm&metric-set permit 20
> match ip add x
> set metric 200
>
> router-map comm&metric-set permit 30
> set metric 200
>
> Router bgp 99
> ....
> Neighbor 10.1.1.1 route-map comm&metric-set out
>
>
> let me know what is the result
>
> -Mamoor
>
>
> ----- Original Message -----
> From: Carl Phelan <carlphelan@hotmail.com>
> To: 'Ouellette, Tim' <tim.ouellette@eds.com>
> Cc: <ccielab@groupstudy.com>
> Sent: Sunday, March 24, 2002 6:36 AM
> Subject: RE: BGP - Transit Area and now Route-Maps
>
>
> > Thanks Tim for the reply. I have a weird problem with BGP.
> I cannot
> > seem to create 2 neighbor statements with route-maps as
> when I enter
> > the second neighbor statement; the first disappears from the config.
> >
> > Here is my set up:
> >
> > R1
> > Route-map set-comm perm 10
> > Set community no-export
> >
> > Route-map metric-set perm 10
> > Match ip ad x
> > Set metric 200
> > ..
> > Route-map metric-set perm 20
> > Set metric 300
> > ..
> > Router bgp 99
> > ....
> > Neighbor 10.1.1.1 route-map set-comm out
> > Neighbor 10.1.1.1 route-map metric-set out
> >
> > But when I look at the config only the last neighbor statement
> > remains, if I add the missing neighbor statement again; the
> existing
> > neighbor statement disappears! The same problem happens on another
> > router but has the additional neighbor statement:
> >
> > Neighbor 11.1.1.1 route-map set-weight in
> > ..
> > Route-map set-weight perm 10
> > Set weight 1000
> >
> > Which stays.
> >
> >
> > I have even tried adding a line 5 in set-metric to add 'set
> community
> > no-export' to join both route-maps into one but the external AS
> > ignores the metric statements. I am running IOS 12.0(10)
> >
> > What gives? All advice would be extremely appreciated!
> >
> >
> >
> > -----Original Message-----
> > From: nobody@groupstudy.com [mailto:nobody@groupstudy.com]
> On Behalf
> > Of Ouellette, Tim
> > Sent: 24 March 2002 00:39
> > To: 'Carl Phelan'
> > Cc: 'ccielab@groupstudy.com'
> > Subject: RE: BGP - Transit Area
> >
> > Try setting a community of no-export on routes incoming
> from both of
> > your ebgp peers. Obviously if your concerned about being
> non-transit
> > then you have multiple connections to the "outside world" with
> > multiple providers.
> >
> > If anyone else has other ways please respond!
> >
> > Tim
> >
> >
> > -----Original Message-----
> > From: Carl Phelan [mailto:carlphelan@hotmail.com]
> > Sent: Saturday, March 23, 2002 12:00 PM
> > To: ccielab@groupstudy.com
> > Subject: BGP - Transit Area
> >
> >
> > Hi All,
> >
> > I am practising doing normal tasks in different ways - as
> expected for
> > the lab. In BGP, what is the simplest way to make an area a
> > non-transit area without using an AS path filter?
> >
> > Many thanks for any advice.
> >
> > Carl
This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 10:57:20 GMT-3