set service dns forwarding authoritative-domain 2.168.192.in-addr.arpa records ptr 36 target mydomain.local
That is the zone is “2.168.192.in-addr.arpa” who then contains “PTR 36 mydomain.local” and is resolved by “nslookup 192.168.2.36” or “dig 36.2.168.192.in-addr.arpa”.