Resolving the name of the firewall
In my System->General, i have specified a hostname and domain for my pfSense firewall. say "edgefirewall.domain.com"
this is not resolvable from the when using the DNS Resolver. shouldn't this be added to the host override list transparently? or to (/etc/hosts) which means I should be able to resolve?
the hostname command works fine locally, but what is the trick to get this to resolve via the firewalls DNS Resolver without adding a host override?
Where you have a LAN interface, that's added to the hosts file to resolve the configured system hostname to the LAN IP. Unbound populates that in /var/unbound/host_entries.conf, which is how clients pointing to the DNS Resolver can resolve that hostname. That all happens by default, and there isn't a way of disabling that. I'm guessing maybe your clients are pointed to something other than the resolver for their DNS, or maybe if you changed it after attempting to do a lookup, the clients are still caching the NXDOMAIN locally.