{ "name": "bbc.co.uk.", "type": "NS", "hops": [ { "zone": ".", "server": "k.root-servers.net.", "server_ip": "193.0.14.129", "rtt": "7.9ms", "rcode": "NOERROR", "authoritative": false, "delegation": "uk.", "referral": [ { "name": "uk.", "type": "NS", "ttl": 172800, "value": "nsa.nic.uk." }, { "name": "uk.", "type": "NS", "ttl": 172800, "value": "nsb.nic.uk." }, { "name": "uk.", "type": "NS", "ttl": 172800, "value": "nsc.nic.uk." }, { "name": "uk.", "type": "NS", "ttl": 172800, "value": "nsd.nic.uk." }, { "name": "uk.", "type": "NS", "ttl": 172800, "value": "dns1.nic.uk." }, { "name": "uk.", "type": "NS", "ttl": 172800, "value": "dns2.nic.uk." }, { "name": "uk.", "type": "NS", "ttl": 172800, "value": "dns3.nic.uk." }, { "name": "uk.", "type": "NS", "ttl": 172800, "value": "dns4.nic.uk." } ], "glue": [ { "name": "nsa.nic.uk.", "type": "A", "ttl": 172800, "value": "156.154.100.3" }, { "name": "nsb.nic.uk.", "type": "A", "ttl": 172800, "value": "156.154.101.3" }, { "name": "nsc.nic.uk.", "type": "A", "ttl": 172800, "value": "156.154.102.3" }, { "name": "nsd.nic.uk.", "type": "A", "ttl": 172800, "value": "156.154.103.3" }, { "name": "dns1.nic.uk.", "type": "A", "ttl": 172800, "value": "213.248.216.1" }, { "name": "dns2.nic.uk.", "type": "A", "ttl": 172800, "value": "103.49.80.1" }, { "name": "dns3.nic.uk.", "type": "A", "ttl": 172800, "value": "213.248.220.1" }, { "name": "dns4.nic.uk.", "type": "A", "ttl": 172800, "value": "43.230.48.1" }, { "name": "nsa.nic.uk.", "type": "AAAA", "ttl": 172800, "value": "2001:502:ad09::3" }, { "name": "nsb.nic.uk.", "type": "AAAA", "ttl": 172800, "value": "2001:502:2eda::3" }, { "name": "nsc.nic.uk.", "type": "AAAA", "ttl": 172800, "value": "2610:a1:1009::3" }, { "name": "nsd.nic.uk.", "type": "AAAA", "ttl": 172800, "value": "2610:a1:1010::3" }, { "name": "dns1.nic.uk.", "type": "AAAA", "ttl": 172800, "value": "2a01:618:400::1" }, { "name": "dns2.nic.uk.", "type": "AAAA", "ttl": 172800, "value": "2401:fd80:400::1" }, { "name": "dns3.nic.uk.", "type": "AAAA", "ttl": 172800, "value": "2a01:618:404::1" }, { "name": "dns4.nic.uk.", "type": "AAAA", "ttl": 172800, "value": "2401:fd80:404::1" } ], "final": false }, { "zone": "uk.", "server": "dns1.nic.uk.", "server_ip": "213.248.216.1", "rtt": "8.5ms", "rcode": "NOERROR", "authoritative": false, "delegation": "bbc.co.uk.", "referral": [ { "name": "bbc.co.uk.", "type": "NS", "ttl": 172800, "value": "dns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 172800, "value": "dns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 172800, "value": "dns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 172800, "value": "dns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 172800, "value": "ddns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 172800, "value": "ddns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 172800, "value": "ddns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 172800, "value": "ddns1.bbc.com." } ], "glue": [ { "name": "dns0.bbc.co.uk.", "type": "A", "ttl": 172800, "value": "198.51.44.9" }, { "name": "dns1.bbc.co.uk.", "type": "A", "ttl": 172800, "value": "198.51.45.9" }, { "name": "ddns0.bbc.co.uk.", "type": "A", "ttl": 172800, "value": "148.163.199.1" }, { "name": "ddns1.bbc.co.uk.", "type": "A", "ttl": 172800, "value": "148.163.199.65" }, { "name": "dns0.bbc.co.uk.", "type": "AAAA", "ttl": 172800, "value": "2620:4d:4000:6259:7:9:0:1" }, { "name": "dns1.bbc.co.uk.", "type": "AAAA", "ttl": 172800, "value": "2a00:edc0:6259:7:9::2" }, { "name": "ddns0.bbc.co.uk.", "type": "AAAA", "ttl": 172800, "value": "2607:f740:e04e::1" }, { "name": "ddns1.bbc.co.uk.", "type": "AAAA", "ttl": 172800, "value": "2607:f740:e04e:4::1" } ], "final": false }, { "zone": "bbc.co.uk.", "server": "dns0.bbc.com.", "server_ip": "198.51.44.73", "rtt": "8.5ms", "rcode": "NOERROR", "authoritative": true, "answer": [ { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.com." } ], "final": true } ], "zone": "bbc.co.uk.", "rcode": "NOERROR", "answer": [ { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.com." } ], "answer_ttl": 900, "parent_ns": [ "ddns0.bbc.co.uk.", "ddns0.bbc.com.", "ddns1.bbc.co.uk.", "ddns1.bbc.com.", "dns0.bbc.co.uk.", "dns0.bbc.com.", "dns1.bbc.co.uk.", "dns1.bbc.com." ], "child_ns": [ "ddns0.bbc.co.uk.", "ddns0.bbc.com.", "ddns1.bbc.co.uk.", "ddns1.bbc.com.", "dns0.bbc.co.uk.", "dns0.bbc.com.", "dns1.bbc.co.uk.", "dns1.bbc.com." ], "authoritative_servers": [ { "name": "dns0.bbc.com.", "ip": "198.51.44.73", "serial": 2026092101, "authoritative": true, "rcode": "NOERROR", "records": [ { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.com." } ], "rtt": "8.6ms", "status": "match" }, { "name": "ddns1.bbc.co.uk.", "ip": "148.163.199.65", "serial": 2026092101, "authoritative": true, "rcode": "NOERROR", "records": [ { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.com." } ], "rtt": "8.4ms", "status": "match" }, { "name": "ddns1.bbc.com.", "ip": "148.163.199.193", "serial": 2026092101, "authoritative": true, "rcode": "NOERROR", "records": [ { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.com." } ], "rtt": "7.8ms", "status": "match" }, { "name": "ddns0.bbc.co.uk.", "ip": "148.163.199.1", "serial": 2026092101, "authoritative": true, "rcode": "NOERROR", "records": [ { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.com." } ], "rtt": "8.4ms", "status": "match" }, { "name": "dns1.bbc.com.", "ip": "198.51.45.73", "serial": 2026092101, "authoritative": true, "rcode": "NOERROR", "records": [ { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.com." } ], "rtt": "131.9ms", "status": "match" }, { "name": "dns0.bbc.co.uk.", "ip": "198.51.44.9", "serial": 2026092101, "authoritative": true, "rcode": "NOERROR", "records": [ { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.com." } ], "rtt": "8.2ms", "status": "match" }, { "name": "ddns0.bbc.com.", "ip": "148.163.199.129", "serial": 2026092101, "authoritative": true, "rcode": "NOERROR", "records": [ { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.com." } ], "rtt": "7.8ms", "status": "match" }, { "name": "dns1.bbc.co.uk.", "ip": "198.51.45.9", "serial": 2026092101, "authoritative": true, "rcode": "NOERROR", "records": [ { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.com." } ], "rtt": "132.1ms", "status": "match" } ], "resolvers": [ { "name": "Cloudflare", "ip": "1.1.1.1", "rcode": "NOERROR", "records": [ { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.com." } ], "ttl": 900, "rtt": "10.7ms", "status": "match", "note": "Same answer, freshly fetched." }, { "name": "Google", "ip": "8.8.8.8", "rcode": "NOERROR", "records": [ { "name": "bbc.co.uk.", "type": "NS", "ttl": 586, "value": "ddns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 586, "value": "ddns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 586, "value": "ddns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 586, "value": "dns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 586, "value": "dns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 586, "value": "dns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 586, "value": "ddns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 586, "value": "dns0.bbc.co.uk." } ], "ttl": 586, "rtt": "8.1ms", "status": "match", "note": "Same answer, cached 5m 14s ago; re-fetches in 9m 46s." }, { "name": "Quad9", "ip": "9.9.9.9", "rcode": "NOERROR", "records": [ { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.com." } ], "ttl": 900, "rtt": "17.7ms", "status": "match", "note": "Same answer, freshly fetched." }, { "name": "OpenDNS", "ip": "208.67.222.222", "rcode": "NOERROR", "records": [ { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "dns1.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns0.bbc.com." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.co.uk." }, { "name": "bbc.co.uk.", "type": "NS", "ttl": 900, "value": "ddns1.bbc.com." } ], "ttl": 900, "rtt": "9.8ms", "status": "match", "note": "Same answer, freshly fetched." } ], "findings": [ { "name": "Authoritative answer", "status": "pass", "value": "ddns0.bbc.co.uk., ddns0.bbc.com., ddns1.bbc.co.uk., ddns1.bbc.com., dns0.bbc.co.uk., dns0.bbc.com., dns1.bbc.co.uk., dns1.bbc.com.", "note": "From the servers for bbc.co.uk., TTL 15m 0s. This is what every resolver converges on." }, { "name": "Delegation", "status": "pass", "value": "8 nameservers", "note": "The parent zone and the zone itself list the same nameservers." }, { "name": "Glue", "status": "pass", "value": "8 of 8 records match", "note": "Every address the parent hands out for the nameservers matches what the zone itself publishes." }, { "name": "Authoritative servers", "status": "pass", "value": "8 of 8 answered", "note": "Every nameserver in the delegation responded." }, { "name": "Zone serial", "status": "pass", "value": "2026092101 on every server", "note": "All nameservers hold the same version of the zone." }, { "name": "Public resolvers", "status": "pass", "value": "4 of 4 match", "note": "Cloudflare, Google, Quad9 and OpenDNS all return the authoritative answer. If a user still sees something else, their ISP's resolver or their own machine is caching it." } ], "summary": "All 4 resolvers agree with the authoritative servers", "dig": "dig +trace +additional bbc.co.uk NS" }