If you really want to have no SPOF you'd probably build something like this: Multihomed IP <-> Loadbalancer <-> Application By having the same setup running o

If you really want to have no SPOF you'd probably build something like this: Multihomed IP <-> Loadbalancer <-> Application By having the same setup running on multiple locations you can replace the load banacers by taking one location offline (stop announcing the corresponding route). Application instances can be replaced by taking the application instance out of the load balancer.