Could you please describe how can I bind 2 different servers to the same IP with automatic request balancing (so when one server is down, another one will serve all requests)? I understand how to do it with another server with HAProxy, but your solution seems to be without HAProxy.
To have 2 servers with the same IP, we use VRRP (Virtual Router Redundancy Protocol) and keepalived. HAProxy is setup on 2 separate servers/instances, and using VRRP/keepalive they both share an IP address (which HAProxy binds to). The servers also have their own unique IP address(es) (on top of the shared one), so the shared address doesn't really "belong" to any machine.
If one server goes down, VRRP gives the IP to the other server and that HAProxy takes over.
