[c-nsp] problem eith EIGRP and BGP

[Oliver Boehmer (oboehmer)]

Sanju,

can you please post your BGP+EIGRP config? Looks like the distance
command didn't take effect, otherwise eBGP wouldn't be preferred after
the EIGRP neighbor flap. The distance command doesn't support a
prefix-list, please use a standard ACL instead.

	oli

sanju shastri <mailto:cuteboysanju at gmail.com> wrote on Tuesday, May 15,
2007 1:08 AM:

> HI Oli,
> 
> Thx for replying , that really a good option . i was not awrae of the
> same. 
> 
> i would like to share my solution with you..
> 
> What i have done i have created a route map in which i have permitted
> the subnets for which i need to change the AD while using a prefix
> list.  
> 
> then i redistributed eigrp into bgp using that route map.
> now what it does i have two route in bgp one from EBGP peer and
> second from the local BGP (this originally came from the eigrp , the
> redistributed one )  
> 
> now the bgp path selection comes into picture and selects the the
> local bgp route coz of higher weight. 
> 
> BGP give ip routing table a local bgp route with AD 200.
> Now routing table selects the route from eigrp coz of lesser AD i.e
> 90 or 170 couls be internal or external. 
> 
> I have achieved the traffic flow from the route learned from the
> eigrp route. 
> 
> But here comes the problem abt convergence , if the EIGRP neighbour
> goes down  then EBGP route comes into effect and traffic goes from it
> bur when it comes back again the routing table does not select the
> eigrp route .   
> 
> Any suggestions what could be cause of problem.
> 
> Regards,
> Sanju
> 
> 
> 
> On 5/13/07, Oliver Boehmer (oboehmer) < oboehmer at cisco.com
> <mailto:oboehmer at cisco.com> > wrote: 
> 
> 	sanju shastri <> wrote on Sunday, May 13, 2007 10:09 AM:
> 
> 	> HI all,
> 	>
> 	> I have a scenario in which a SP is giving L3 MPLS VPN to
client
> 	having > multiple locations.
> 	>
> 	> Now thw client is running EIGRP in his network and EBGP with
SP.
> 	>
> 	>
> 	> ON HUB location routes learned by router for remote branches
via
> 	> EIGRP is having an AD of 90 and learnned from EBGP are having
a AD
> 	of > 20. Becasuse of same the EBGP routes are given preference
in
> 	any case. >
> 	> The client wants to give preference to routeds leaned by local
> 	EIGRP > and want to make MPLS VPN link as a failover/secondary.
> 	>
> 	> well I can change AD for the EBGP session but it will
reflected to
> 	> all the subnet where i want it for some specific subnet.
> 
> 	you can selectively adjust the distance for specific subnets
using
> the 
> 
> 	distance <distance> 0.0.0.0 255.255.255.255 <acl>
> 
> 	command (within router bgp), where you define the networks you
want
> 	to change the distance of in the access-list referenced there.
> 
> 	Not knowing details about the topology, but you might also be
> 	successful when you increase eBGP admin distance from 20 to 100
or
> 	so, which is higher than EIGRP internal distance (90), but lower
> 	than EIGRP's external one (170). This way, only internal EIGRP
> 	prefixes (i.e. originated within the same site) are preferred,
while
> 	external ones (possibly received from remote sites via the
L3VPN)
> 	are preferred through the local eBGP connection (with a backup
to
> 	the redundant hub router redistributing those into EIGRP).
> 
> 	        oli