Trouble Advertising same subnet across multiple MPLS, Multiple DCs

[MJRodman21]

To keep it super simple, I have the following:

Two Data Centers that have a static path to a subnet through a private connection - that subnet is 10.80.0.0/16

Each data center attaches to two different MPLS Providers, each of those have a single router in the DCs. 4 DC MPLS Routers, two in each location...

Branch Office has one router from each MPLS router (two routers total).

I'm trying to steer this subnet - 10.80.0.0/16 through a particular data center, and BGP is automatically taking the unpreferred path (I know, it's probably taking the better path, but management wants certain offices to go through certain data centers)

I know a pre-pend would help if I had two different subnets, so I don't think that's the way.

I'm thinking I need to tell my Data Center BGP Routers in the preferred data center, that the path to it's router has a higher weight than the other routers. How can I go about doing that?

If that's not the right method to use, I'm truly stumped.

[Giuseppe Larosa]

Hello @MJRodman21 ,

AS path prepending of the Branch router towards the SP provider that should not be used should work.

All you need is a route-map that invokes a prefix-list matching the prefix to be made prepended.

on DC side you coould increase the local preference on the "right" DC if there is i BGP between the two DCs

Hope to help

Giuseppe