./fake-ns -d xxx.com> nslookup 127.0.0.1.fns.inurl.org 8.8.8.8
Server: 8.8.8.8
Address: 8.8.8.8#53
Non-authoritative answer:
Name: 127.0.0.1.fns.inurl.org
Address: 127.0.0.1
> nslookup 0xffffffff.fns.inurl.org 8.8.8.8
Server: 8.8.8.8
Address: 8.8.8.8#53
Non-authoritative answer:
Name: 0xffffffff.fns.inurl.org
Address: 255.255.255.255
> nslookup 2130706433.fns.inurl.org 8.8.8.8
Server: 8.8.8.8
Address: 8.8.8.8#53
Non-authoritative answer:
Name: 2130706433.fns.inurl.org
Address: 127.0.0.1