Using alternate ports:

DNS resolvers typically run on UDP/53 and TCP/53. Often software that modifies DNS requests will be looking for those protocol/port combinations. DNS Paranoia is also running its resolvers on UDP/10053 and TCP/10053. A behavior change - if you get one answer on 53 and a different one on 10053, may indicate interference on the default port.


Syntax:

dig -p10053 @dnsp.co www.example.org
nslookup -port=10053 www.example.org dnsp.co

Example, using '-p 10053' to query on alternate port:

prompt> dig -p 10053 @dnsp.co www.google.com ; <<>> DiG 9.5.0-P2 <<>> -p 10053 @dnsp.co www.google.com ; (1 server found) ;; global options: printcmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 372 ;; flags: qr aa ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0 ;; QUESTION SECTION: ;www.google.com. IN A ;; ANSWER SECTION: www.google.com. 0 IN A 123.45.67.89 ;; Query time: 33 msec ;; SERVER: 192.155.94.246#10053(192.155.94.246) ;; WHEN: Mon Dec 22 02:03:11 2014 ;; MSG SIZE rcvd: 48