well as its 3yrs old you might still get some support from Apple.
Also id consider taking it back to the supplier and explaining the issue.
Have you looked into the built in backup (time machine) for Apple. It is a built in rsync to what ever destination you wish, be it local, external, LAN, or WAN locations.
you can always manually populate /etc/hosts with IP/name:
imac:~ user$ cat /etc/hosts
# Host Database
# localhost is used to configure the loopback interface
# when the system is booting. Do not change this entry.
thats my hosts file on my iMac.