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DNS lookup

Everything DNS says about a domain: traced from the root servers down, every record type asked of the domain's own nameservers, each nameserver checked, then every hostname and policy record it points at followed, with SPF, DMARC, DKIM and DNSSEC checked along the way.

Try example.com, gmail.com, www.github.com, dnssec-failed.org, 1.1.1.1. A URL, e-mail address or IP address works too.

2a00:1450:4001:c1f::8b

b.8.0.0.0.0.0.0.0.0.0.0.0.0.0.0.f.1.c.0.1.0.0.4.0.5.4.1.0.0.a.2.ip6.arpa

Zone 0.5.4.1.0.0.a.2.ip6.arpa90 queries in 1.1 s2026-11-09 05:45:22 UTCNot DNSSEC-signed

WHOIS for 2a00:1450:4001:c1f::8b →TextJSON
  • Note 0.5.4.1.0.0.a.2.ip6.arpa isn't signed with DNSSEC, so resolvers can't tell forged answers from real ones.

Records

Asked directly of ns4.google.com (216.239.38.10), an authoritative server: no cache in between, so these are the live values.

PTR Reverse pointer

3600PTRbz-in-f139.1e100.net.
ANY query: 1 records
3600PTRbz-in-f139.1e100.net.

No records of type A, AAAA, CNAME, DNAME, NS, SOA, MX, TXT, CAA, HTTPS, SVCB, SRV, NAPTR, DS, DNSKEY, CDS, CDNSKEY, NSEC3PARAM, TLSA, SSHFP, LOC, HINFO, RP, URI, SPF, OPENPGPKEY, ZONEMD, CSYNC.

Resolution trace

  1. .asked j.root-servers.net 192.58.128.3038 ms

    Referral to ip6.arpa. signed (3 DS)

    • a.ip6-servers.arpa 199.180.182.53 2620:37:e000::53
    • b.ip6-servers.arpa 199.253.182.182 2001:500:86::86
    • c.ip6-servers.arpa 196.216.169.11 2001:43f8:110::11
    • d.ip6-servers.arpa 200.7.86.53 2001:13c7:7012::53
    • e.ip6-servers.arpa 203.119.86.101 2001:dd8:6::101
    • f.ip6-servers.arpa 193.0.9.2 2a13:27c0:30::2
  2. ip6.arpa.asked a.ip6-servers.arpa 199.180.182.5390 ms

    Referral to 0.a.2.ip6.arpa. signed (1 DS)

    • rirns.arin.net 199.253.249.53 2620:38:2000::53
    • ns3.afrinic.net 204.61.216.100 2001:500:14:6100:ad::1
    • pri.authdns.ripe.net 193.0.9.5 2a13:27c0:30::5
    • ns4.apnic.net 202.12.31.53 2001:dd8:12::53
    • ns3.lacnic.net 200.3.13.14 2001:13c7:7002:3000::14

    No glue for rirns.arin.net, ns3.afrinic.net, pri.authdns.ripe.net, ns4.apnic.net, ns3.lacnic.net: addresses looked up via a resolver.

  3. 0.a.2.ip6.arpa.asked rirns.arin.net 199.253.249.5390 ms

    Referral to 0.5.4.1.0.0.a.2.ip6.arpa. unsigned delegation

    • ns4.google.com 216.239.38.10 2001:4860:4802:38::a
    • ns1.google.com 216.239.32.10 2001:4860:4802:32::a
    • ns2.google.com 216.239.34.10 2001:4860:4802:34::a
    • ns3.google.com 216.239.36.10 2001:4860:4802:36::a

    No glue for ns4.google.com, ns1.google.com, ns2.google.com, ns3.google.com: addresses looked up via a resolver.

    200.3.13.14 failed: NOERROR

  4. 0.5.4.1.0.0.a.2.ip6.arpa.asked ns3.google.com 216.239.36.1013 ms

    Answer (authoritative):

    b.8.0.0.0.0.0.0.0.0.0.0.0.0.0.0.f.1.c.0.1.0.0.4.0.5.4.1.0.0.a.2.ip6.arpa.3600PTRbz-in-f139.1e100.net.

Nameservers

Every address of every nameserver, asked for 0.5.4.1.0.0.a.2.ip6.arpa's SOA. "Parent" means the 0.a.2.ip6.arpa zone delegates to it; "zone" means 0.5.4.1.0.0.a.2.ip6.arpa lists it itself.

NameserverListed inAddressStatusSerialTime
ns1.google.comparent + zone216.239.32.10 glueauthoritative101668721014 ms
2001:4860:4802:32::a glueauthoritative101668721014 ms
ns2.google.comparent + zone216.239.34.10 glueauthoritative101668721027 ms
2001:4860:4802:34::a glueauthoritative101668721027 ms
ns3.google.comparent + zone216.239.36.10 glueauthoritative101668721015 ms
2001:4860:4802:36::a glueauthoritative101668721013 ms
ns4.google.comparent + zone216.239.38.10 glueauthoritative10166872106.8 ms
2001:4860:4802:38::a glueauthoritative10166872107.1 ms

DNSSEC

0.5.4.1.0.0.a.2.ip6.arpa isn't signed: no DS at the parent and no DNSKEY in the zone.

Hosts and reverse DNS

Every hostname the records point at, resolved to its addresses; each address's PTR (reverse DNS), with ✓ where the PTR name resolves back to the same address.

HostAddressReverse DNS (PTR)
ns1.google.com
nameserver
216.239.32.10ns1.google.com ✓
2001:4860:4802:32::ans1.google.com ✓
ns2.google.com
nameserver
216.239.34.10ns2.google.com ✓
2001:4860:4802:34::ans2.google.com ✓
ns3.google.com
nameserver
216.239.36.10ns3.google.com ✓
2001:4860:4802:36::ans3.google.com ✓
ns4.google.com
nameserver
216.239.38.10ns4.google.com ✓
2001:4860:4802:38::ans4.google.com ✓
bz-in-f139.1e100.net
PTR target
142.251.110.139bz-in-f139.1e100.net ✓
2a00:1450:4001:c1f::8bbz-in-f139.1e100.net ✓

Public resolvers

What four public resolvers answer right now, from their caches. Highlighted values differ from the authoritative answer: either a recent change they haven't picked up yet (the TTL says how long until they do), or, for A and AAAA, a CDN or geo-routed site handing each resolver location its own addresses.

ResolverPTR
Cloudflare 1.1.1.1bz-in-f139.1e100.net.
TTL 523
Google 8.8.8.8bz-in-f139.1e100.net.
TTL 2371
Quad9 9.9.9.9bz-in-f139.1e100.net.
TTL 972
OpenDNS 208.67.222.222bz-in-f139.1e100.net.
TTL 3600

Text dump

; DNS report for b.8.0.0.0.0.0.0.0.0.0.0.0.0.0.0.f.1.c.0.1.0.0.4.0.5.4.1.0.0.a.2.ip6.arpa (2a00:1450:4001:c1f::8b)
; 2026-11-09 05:45:22 UTC, 90 queries in 1.12 s, zone 0.5.4.1.0.0.a.2.ip6.arpa

;; FINDINGS
;  [INFO] 0.5.4.1.0.0.a.2.ip6.arpa isn't signed with DNSSEC, so resolvers can't tell forged answers from real ones.

;; RECORDS (authoritative, from ns4.google.com (216.239.38.10))
b.8.0.0.0.0.0.0.0.0.0.0.0.0.0.0.f.1.c.0.1.0.0.4.0.5.4.1.0.0.a.2.ip6.arpa.	3600	IN	PTR	bz-in-f139.1e100.net.

;; TRACE
;  b.8.0.0.0.0.0.0.0.0.0.0.0.0.0.0.f.1.c.0.1.0.0.4.0.5.4.1.0.0.a.2.ip6.arpa PTR
;  . @j.root-servers.net (192.58.128.30) 38 ms [NOERROR qr]: referral to ip6.arpa.
ip6.arpa.		NS	a.ip6-servers.arpa.	; 199.180.182.53 2620:37:e000::53
ip6.arpa.		NS	b.ip6-servers.arpa.	; 199.253.182.182 2001:500:86::86
ip6.arpa.		NS	c.ip6-servers.arpa.	; 196.216.169.11 2001:43f8:110::11
ip6.arpa.		NS	d.ip6-servers.arpa.	; 200.7.86.53 2001:13c7:7012::53
ip6.arpa.		NS	e.ip6-servers.arpa.	; 203.119.86.101 2001:dd8:6::101
ip6.arpa.		NS	f.ip6-servers.arpa.	; 193.0.9.2 2a13:27c0:30::2
ip6.arpa.	86400	IN	DS	13880 8 2 068554EFCB5861F42AF93EF8E79C442A86C16FC5652E6B6D2419ED527F344D17
ip6.arpa.	86400	IN	DS	45094 8 2 E6B54E0A20CE1EDBFCB6879C02F5782059CECB043A31D804A04AFA51AF01D5FB
ip6.arpa.	86400	IN	DS	64060 8 2 8A11501086330132BE2C23F22DEDF0634AD5FF668B4AA1988E172C6A2A4E5F7B
;  ip6.arpa. @a.ip6-servers.arpa (199.180.182.53) 90 ms [NOERROR qr]: referral to 0.a.2.ip6.arpa.
0.a.2.ip6.arpa.		NS	rirns.arin.net.	; 199.253.249.53 2620:38:2000::53
0.a.2.ip6.arpa.		NS	ns3.afrinic.net.	; 204.61.216.100 2001:500:14:6100:ad::1
0.a.2.ip6.arpa.		NS	pri.authdns.ripe.net.	; 193.0.9.5 2a13:27c0:30::5
0.a.2.ip6.arpa.		NS	ns4.apnic.net.	; 202.12.31.53 2001:dd8:12::53
0.a.2.ip6.arpa.		NS	ns3.lacnic.net.	; 200.3.13.14 2001:13c7:7002:3000::14
0.a.2.ip6.arpa.	86400	IN	DS	6737 13 2 F346C2BE7A1D04F367DC2B24556FA5F6AE515F4C005C7D44508B31E8D79C9694
;  0.a.2.ip6.arpa. @rirns.arin.net (199.253.249.53) 90 ms [NOERROR qr]: referral to 0.5.4.1.0.0.a.2.ip6.arpa.
0.5.4.1.0.0.a.2.ip6.arpa.		NS	ns4.google.com.	; 216.239.38.10 2001:4860:4802:38::a
0.5.4.1.0.0.a.2.ip6.arpa.		NS	ns1.google.com.	; 216.239.32.10 2001:4860:4802:32::a
0.5.4.1.0.0.a.2.ip6.arpa.		NS	ns2.google.com.	; 216.239.34.10 2001:4860:4802:34::a
0.5.4.1.0.0.a.2.ip6.arpa.		NS	ns3.google.com.	; 216.239.36.10 2001:4860:4802:36::a
;  0.5.4.1.0.0.a.2.ip6.arpa. @ns3.google.com (216.239.36.10) 13 ms [NOERROR qr aa]: answer
b.8.0.0.0.0.0.0.0.0.0.0.0.0.0.0.f.1.c.0.1.0.0.4.0.5.4.1.0.0.a.2.ip6.arpa.	3600	IN	PTR	bz-in-f139.1e100.net.

;; NAMESERVERS (SOA asked of each address)
;  ns1.google.com [parent+zone]
;    216.239.32.10                           ok                        1016687210  14 ms
;    2001:4860:4802:32::a                    ok                        1016687210  14 ms
;  ns2.google.com [parent+zone]
;    216.239.34.10                           ok                        1016687210  27 ms
;    2001:4860:4802:34::a                    ok                        1016687210  27 ms
;  ns3.google.com [parent+zone]
;    216.239.36.10                           ok                        1016687210  15 ms
;    2001:4860:4802:36::a                    ok                        1016687210  13 ms
;  ns4.google.com [parent+zone]
;    216.239.38.10                           ok                        1016687210  6.8 ms
;    2001:4860:4802:38::a                    ok                        1016687210  7.1 ms

;; DNSSEC: unsigned

;; HOSTS
;  ns1.google.com (nameserver)
;    216.239.32.10                           PTR ns1.google.com (confirmed)
;    2001:4860:4802:32::a                    PTR ns1.google.com (confirmed)
;  ns2.google.com (nameserver)
;    216.239.34.10                           PTR ns2.google.com (confirmed)
;    2001:4860:4802:34::a                    PTR ns2.google.com (confirmed)
;  ns3.google.com (nameserver)
;    216.239.36.10                           PTR ns3.google.com (confirmed)
;    2001:4860:4802:36::a                    PTR ns3.google.com (confirmed)
;  ns4.google.com (nameserver)
;    216.239.38.10                           PTR ns4.google.com (confirmed)
;    2001:4860:4802:38::a                    PTR ns4.google.com (confirmed)
;  bz-in-f139.1e100.net (PTR target)
;    142.251.110.139                         PTR bz-in-f139.1e100.net (confirmed)
;    2a00:1450:4001:c1f::8b                  PTR bz-in-f139.1e100.net (confirmed)

;; PUBLIC RESOLVERS
;  Cloudflare PTR   bz-in-f139.1e100.net.  ttl 523
;  Google     PTR   bz-in-f139.1e100.net.  ttl 2371
;  Quad9      PTR   bz-in-f139.1e100.net.  ttl 972
;  OpenDNS    PTR   bz-in-f139.1e100.net.  ttl 3600