Latest github NS moved to awsdns
$ dig -tNS github.com @8.8.8.8
; <<>> DiG 9.8.3-P1 <<>> -tNS github.com @8.8.8.8
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 15616
;; flags: qr rd ra; QUERY: 1, ANSWER: 8, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;github.com. IN NS
;; ANSWER SECTION:
github.com. 899 IN NS ns-1283.awsdns-32.org.
github.com. 899 IN NS ns-1707.awsdns-21.co.uk.
github.com. 899 IN NS ns-421.awsdns-52.com.
github.com. 899 IN NS ns-520.awsdns-01.net.
github.com. 899 IN NS ns1.p16.dynect.net.
github.com. 899 IN NS ns2.p16.dynect.net.
github.com. 899 IN NS ns3.p16.dynect.net.
github.com. 899 IN NS ns4.p16.dynect.net.
;; Query time: 32 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Fri Oct 21 13:01:48 2016
;; MSG SIZE rcvd: 248
$ dig -tNS twitter.com
; <<>> DiG 9.8.3-P1 <<>> -tNS twitter.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 62729
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 4
;; QUESTION SECTION:
;twitter.com. IN NS
;; ANSWER SECTION:
twitter.com. 75575 IN NS ns3.p34.dynect.net.
twitter.com. 75575 IN NS ns4.p34.dynect.net.
twitter.com. 75575 IN NS ns1.p34.dynect.net.
twitter.com. 75575 IN NS ns2.p34.dynect.net.
;; ADDITIONAL SECTION:
ns3.p34.dynect.net. 54698 IN A 208.78.71.34
ns4.p34.dynect.net. 81779 IN A 204.13.251.34
ns1.p34.dynect.net. 8544 IN A 208.78.70.34
ns2.p34.dynect.net. 54775 IN A 204.13.250.34
;; Query time: 0 msec
;; SERVER: <local>
;; WHEN: Fri Oct 21 13:02:14 2016
;; MSG SIZE rcvd: 179