MPLS Ingress (PE-CE) traffic redundancy

i have 2 separate sites which is currently connected to a service provider’s mpls network. One site has the primary datacenter and the other a DR site. The question is here how do i do the routing to enable other sites/branches connected to the MPLS network to recognize the sites as primary and DR. Do i play aroung with the BGP local preference. I need all the traffic from branches to go the DR site once the primary site is down.