1. TLD/org/isc.org

/sns-pb.isc.org

$ dnsq ns isc.org a.root-servers.net

2 isc.org:
427 bytes, 1+0+6+12 records, response, noerror
query: 2 isc.org
authority: org 172800 NS a0.org.afilias-nst.info
authority: org 172800 NS a2.org.afilias-nst.info
authority: org 172800 NS b0.org.afilias-nst.org
authority: org 172800 NS b2.org.afilias-nst.org
authority: org 172800 NS c0.org.afilias-nst.info
authority: org 172800 NS d0.org.afilias-nst.org
additional: a0.org.afilias-nst.info 172800 A 199.19.56.1
additional: a2.org.afilias-nst.info 172800 A 199.249.112.1
additional: b0.org.afilias-nst.org 172800 A 199.19.54.1
additional: b2.org.afilias-nst.org 172800 A 199.249.120.1
additional: c0.org.afilias-nst.info 172800 A 199.19.53.1
additional: d0.org.afilias-nst.org 172800 A 199.19.57.1
additional: a0.org.afilias-nst.info 172800 AAAA 2001:500:e::1
additional: a2.org.afilias-nst.info 172800 AAAA 2001:500:40::1
additional: b0.org.afilias-nst.org 172800 AAAA 2001:500:c::1
additional: b2.org.afilias-nst.org 172800 AAAA 2001:500:48::1
additional: c0.org.afilias-nst.info 172800 AAAA 2001:500:b::1
additional: d0.org.afilias-nst.org 172800 AAAA 2001:500:f::1

$ dnsq ns isc.org 199.19.56.1

2 isc.org:
256 bytes, 1+0+4+6 records, response, noerror
query: 2 isc.org
authority: isc.org 86400 NS ord.sns-pb.isc.org
authority: isc.org 86400 NS ns.isc.afilias-nst.info
authority: isc.org 86400 NS ams.sns-pb.isc.org
authority: isc.org 86400 NS sfba.sns-pb.isc.org
additional: ams.sns-pb.isc.org 86400 A 199.6.1.30
additional: ams.sns-pb.isc.org 86400 AAAA 2001:500:60::30
additional: ord.sns-pb.isc.org 86400 A 199.6.0.30
additional: ord.sns-pb.isc.org 86400 AAAA 2001:500:71::30
additional: sfba.sns-pb.isc.org 86400 A 149.20.64.3
additional: sfba.sns-pb.isc.org 86400 AAAA 2001:4f8::2:0:0:0:19