I'm currently building a MPLS-network for my company, and one of our goals is to reduce the number of internet-connections. There has been a lot of different internet solutions, and we have at least two AS's that needs to live a a few months into the new solution. One of my AS's needs to live in a VRF in the MPLS-network. Problem is that this is not the same AS as the MPLS-network. I am trying to set up a few eBGP-peerings with our Internet peering-partners, but my AS-path looks a bit strange - My AS-path will be like OLD-AS MPLS-AS OLD-AS i, but I would like to advertise only my OLD-AS with theese updates. Anyone got a solution for that?
The size of a given network and its service complexity of the servics offered, dictates the solution.
Since you are an insider and aware, you are free to choose from the available options discussed.
All of the discussed options will work.
Best of luck.