I have a customer who asked me what happens when his MPLS goes down. I told him that he would have the most recent replication that has happened is what he would have to work with. since he will be running an active passive model to a hosted data center he just needs to make sure that the replication of the Protected VM's is happening at a manageable RPO for the business.
I guess the real question I have is around the DNS. he said the public DNS is also on the MPLS or WAN. So what would he need to do to protect that in the event of a fail over?