What problem are you trying to solve? Depending on what problem you want to solve there are different solutions. You need to consider that with masquerading and internal names, the machine may not know its external IP address and FQDN. The name or IP address its gives may not be accessible to the world.

For example, "hostname" on my home machine gives "kraken". Not a domain name that could be looked up by anyone external. A local lookup or querying the interfaces would give "192.168.1.10". The machine has no clue what someone on the other side of the masquerading firewall would get; the IP address changes with DHCP leases.