nginx only listens to IPv4
I set up an omnibus installation last night at a friends house.
Today at home, it wasn't working. I could not possible find out why I could not connect. After a long period of pointlessly testing everything network-related, I discovered that nginx is misconfigured to only listen to IPv4 out-of-the-box. Since my home connection is pure-IPv6, it was impossible to reach the gitlab installation.
The default should listen to both IPv4 and IPv6 by default, since otherwise many users will be incapable of reaching gitlab installations. note that, since IPv6 records exists for my domain, transition mechanism (ie: NAT64) don't interfere and route translate to IPv4.