Hi, The only moment HAProxy tries to resolve the IP of a hostname found in the conf is at startup. So if it can't find a way to reach the server at this moment, then HAProxy refuses to startup because it knows he will never be able to reach it.
Note, there may be some improvement on this point soon. I know Willy has something in mind: HAProxy will be able to perform a DNS check during the healh check. I have no idea when this will be available. Cheers
