I don't get the DNS connection. I mean, this is a stand alone server, there's no DNS management, I didn't connect it to my DNS cluster (and I don't want to do that). In fact, there's no DNS server installed !
The hostname I used is already defined in my DNS cluster and correctly pointing to this box. I also tried to add the hostname IP in /etc/hosts, just in case.
I just tried now to install DNS server app locally and also have now a correctly defined zone.