03-06-2023 07:24 AM
Hi all
I am facing a weird case. I do have two BGP sessions with two different routers (rtr2 and rtr3 from rtr1) connected via a LAN.
rtr2 rtr3
* *
* *
******
*
*
rtr1
rtr2 and rtr3 were running hsrp on this LAN and rtr1 had a static default route to the VIP. As it was creating routing issues in termes of redundancy I did BGP default-information originate and deleted the static default route so BGP can handle that.
The issue is that I am receiving two default routes from each router. One with the routers next-hop (rtr1 and rtr2 IPs) and one with the VIP as the next-hop advertised by both routers with a 100 local-preference. I don t have any BGP peering with the VIP.
I can workarround this issue by increasing the local-pref of routers but I dont understand why this is happening.
Any ideas ?
Regards
03-06-2023 07:45 AM - edited 03-06-2023 07:58 AM
https://www.cisco.com/c/en/us/support/docs/ip/border-gateway-protocol-bgp/13768-hsrp-bgp.html
this link for Your Information
03-06-2023 07:50 AM - edited 03-06-2023 07:51 AM
Hello
How are you peering between the three rtrs do they share the same ASN or have separate BGP domains?
Or are rtrs 2/3 in the same domain only, either way Rtr should chose just the one default to enter the GRT.
03-06-2023 07:51 AM
rtr2 and rtr3 are in the same AS.
Regards
03-06-2023 07:56 AM
Hello
So unless you have maximum-paths specified then as I stated only a single default should get entered into the global routing table of the RTR1
Can you share your bgp CFG please
All rtrs
sh run | sec router
03-06-2023 08:02 AM
Thanks for your answer. I do have maximum-path 2 enabled on rtr1 but the route from vip is not installed in the RIB because of the local-pref (-). Which I don't understand is why I do receive a route as a VIP as next-hop with no HSRP enabled on this LAN ( as I disabled it) ?
03-06-2023 08:53 AM - edited 03-06-2023 08:56 AM
Hello
@Louey wrote:
Thanks for your answer. I do have maximum-path 2 enabled on rtr1 but the route from vip is not installed in the RIB because of the local-pref (-). Which I don't understand is why I do receive a route as a VIP as next-hop with no HSRP enabled on this LAN ( as I disabled it) ?
Based on what you have described you should not be receiving should a route, hence why i requested you post the bgp cfg of all 3 rtrs.
sh run | sec router
sh ip bgp
sh ip bgp summary
sh ip route bgp
sh ip bgp 0.0.0.0
03-06-2023 08:00 AM
the neighbor is static config or it dynamic with listen group
are you use any listen group
03-06-2023 08:04 AM
I have 2 static BGP neighbor rtr2 and rtr3.
Thanks
03-06-2023 08:07 AM
are the connection is iBGP between these routers ??
03-06-2023 08:14 AM
ebgp
03-06-2023 08:17 AM
I will run lab and see,
the next-hop must be same peer you config not VIP of far HSRP group
but let me check
03-06-2023 08:35 AM
I run lab and as I guess,
the next-hop is Peer IP you config there is no VIP
are you use some kind of route server ??
are you use unchange next-hop ??
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