BGP Multi-homing on Cisco IOS XR , underlying LF and AS-PATH

Ibrahim Jamil · ‎04-07-2016

Hi Cisco Folks

Do you have config example from BGP Multi-homing on Cisco IOS XR , underlying LF and AS-PATH

Thanks

Philip D'Ath · ‎04-11-2016

What does LF mean?

What do you want to do with the AS-PATH?

Do you want to load balance, or do failover?

What is the IP address of your two neighbours, and what are their AS numbers, and what is your AS number?

Ibrahim Jamil · ‎04-12-2016

Hi Philip

sorry mate . my mistake i must say LP not LF , its local preference

1. ASR-1 should announce 91.X.X.X/24 to ISP1 While ISP-2 will be the backup for 91.X.X.X/24

2. ASR-2 should announce 92.X.X.X/24 to ISP2 While ISP-1 will be the backup for 92.X.X.X/24

3. i am getting default route from both ISPs

attached topology

thanks

Philip D'Ath · ‎04-12-2016

That is asking a lot! How about I give you the majority of the solution and you tweak it from there.

Router 1:

router bgp <your asn>
  neighbor 172.16.1.x remote-as <ISP1 ASN>
  neighbor 172.16.1.x description ISP1
  neighbour <internal neighbor ip> remote-as <your own ASN>

  address-family ipv4
    network 91.x.x.x mask 255.255.255.0
    network 92.x.x.x mask 255.255.255.0
    network 172.16.1.x mask 255.255.255.252
    neighbor 172.16.1.x activate
    neighbor 172.16.1.x soft-reconfiguration inbound
    neighbor 172.16.1.x prefix-list company-out
    neighbor 172.16.1.x route-map isp1-in in
    neighbor 172.16.1.x route-map isp1-out out
    neighbour <internal neighbor ip> activate
    neighbour <internal neighbor ip> soft-reconfiguration inbound

ip prefix-list company-out seq 5 permit 91.x.x.x/24
ip prefix-list company-out seq 10 permit 92.x.x.x/24

route-map isp1-in permit 10
 set local-preference 110 <-- set (or don't set) whatever preference you want
 set community local-AS


ip prefix isp1-backup-routes permit x.x.x.x/24

route-map isp1-out permit 10
  match ip address prefix-list isp1-backup-routes
  set as-path prepend <your ASN> <your ASN> <your ASN>
route-map isp1-out permit 20

Ibrahim Jamil · ‎04-12-2016

Hi bro philip

i am okay with these IOS syntax , but bro , the above wont work with IOS XR

mate no route-map on XR but RPL

thanks a lot bro