BGP Conditional Community

Hello All,

I am sensing a very uniqe requirement (at least to me) in one of my project deployments.

I need to be able to track MPLS routes in a CE and if they are unavailable (link down or routes not received) then the CE should request an adjacent router, which also has a leg in MPLS topology, to start advertising its routes.

Meaning a backup path should trigger from CE2 if CE1 has MPLS link failed and it flags (somehow) to CE2 that it can advertise CE1s route present in RIB to PE2. In normal conditions when CE1 has got MPLS up, CE2 can advertise CE1 routes everywhere 'except' PE2 (loop prevention).

I was thinking of BGP conditional and have been partially successful. Since I have no control over MPLS domain, I can append community to inbound routes. Then via another route map I match that community in RIB and if exist, I advertise local CE1 routes with another community to CE2. CE2 filters that community to be advertised to PE2 and allows the rest.

Thats all good but problem is when MPLS is down, the advertisement to CE2 stops. CE1 should be able to advertise routes without community in case of MPLS down and with community if MPLS is up.

Any help will be appreciated.

Thanks.