3751.dk is a .dk domain served by 2 nameservers (ns01.one.com, ns02.one.com). It was registered on 22 August 2002 (WHOIS) and was already in the .dk zone when our tracking began on 16 June 2026. Its website address 37.128.208.15 is hosted by Sinal A/S (AS39642) in Denmark. Mail is handled by mx1.pub.mailpod9-cph3.one.com, mx2.pub.mailpod9-cph3.one.com and 2 more. The zone is DNSSEC-signed but currently fails validation, has no DMARC policy and has no IPv6 address. Below are all of its DNS records from this scan: nameservers, A/AAAA, MX, TXT, SPF, DMARC, CAA, TLSA/DANE, MTA-STS, SRV and more.
| IP | TTL | PTR | ASN | ISP / Org | CIDR | Country | City |
|---|---|---|---|---|---|---|---|
| 37.128.208.15 | 3600s | — | AS39642 | Sinal A/S | 37.128.208.0/20 | 🇩🇰 Denmark | Esbjerg |
| Priority | TTL | Mail Server | IP addresses | PTR | ASN |
|---|---|---|---|---|---|
| 10 | 10800s | mx1.pub.mailpod9-cph3.one.com | 185.164.14.118 | mx1.pub.mailpod9-cph3.one.com | AS51468 One.com A/S |
| 10 | 10800s | mx2.pub.mailpod9-cph3.one.com | 185.164.14.119 | mx2.pub.mailpod9-cph3.one.com | AS51468 One.com A/S |
| 10 | 10800s | mx3.pub.mailpod9-cph3.one.com | 185.164.14.120 | mx3.pub.mailpod9-cph3.one.com | AS51468 One.com A/S |
| 10 | 10800s | mx4.pub.mailpod9-cph3.one.com | 185.164.14.124 | mx4.pub.mailpod9-cph3.one.com | AS51468 One.com A/S |
| www CNAME | 3751.dk (all on 3751.dk) → 37.128.208.15 (AS39642) |
| www vs bare domain | Same network |
| Wildcard | No |
| Denial of existence | NSEC3 · 0 iterations · no salt RFC 9276 ✓ |
| CDS / CDNSKEY | None 0 CDS, 0 CDNSKEY |
| Service / Owner | Type | Cert association |
|---|---|---|
| SMTP _25._tcp.mx1.pub.mailpod9-cph3.one.com | DANE-EE · SPKI · SHA-256 | 5D2162F5CED0ACD2C3D63E5582045A6C… |
| SMTP _25._tcp.mx2.pub.mailpod9-cph3.one.com | DANE-EE · SPKI · SHA-256 | 5D2162F5CED0ACD2C3D63E5582045A6C… |
| SMTP _25._tcp.mx3.pub.mailpod9-cph3.one.com | DANE-EE · SPKI · SHA-256 | 5D2162F5CED0ACD2C3D63E5582045A6C… |
| SMTP _25._tcp.mx4.pub.mailpod9-cph3.one.com | DANE-EE · SPKI · SHA-256 | 5D2162F5CED0ACD2C3D63E5582045A6C… |
| Check | Result |
|---|---|
| Validation Status | ⚠️ Bogus |
| AD Flag (resolver validates) | ✗ Not set |
| DS Record | ✓ Found |
| DNSKEY Record | ✓ Found |
| Flags | broken trust chain resolving '3751.dk/DNSKEY/IN': 127.0.0.1#53 |
| Field | Value |
|---|---|
| Serial | 2026062302 |
| Primary NS (MNAME) | ns01.one.com |
| Responsible (RNAME) | hostmaster@one.com |
| Refresh | 14400s |
| Retry | 3600s |
| Expire | 1209600s |
| Minimum (neg-cache TTL) | 600s |
| Field | Value |
|---|---|
| Registrar | ONE.COM A/S |
| Registered | 2002-08-22 |
| Expires | 2027-09-30 (348d) |
Other .dk domains whose WHOIS registrant has the same name and postal address. Matched on a keyed hash: the registrant's details are not stored or shown. Covers only domains whose WHOIS we have fetched (refreshed about monthly).
No other domain with this registrant in our WHOIS data yet| Scanned At | Duration | Records | DNSSEC |
|---|---|---|---|
| 2026-10-16 10:54:41 | 1371ms | 2 NS 1 A 4 MX | 🔒 Secure |
| 2026-10-12 21:11:21 | 948ms | 2 NS 1 A 4 MX | 🔒 Secure |
| 2026-10-03 07:31:57 | 462ms | 2 NS 1 A 4 MX | 🔒 Secure |
| 2026-09-16 10:36:12 | 700ms | 2 NS 1 A 4 MX | 🔒 Secure |
| 2026-09-10 23:00:24 | 1002ms | 2 NS 1 A 4 MX | 🔒 Secure |
| 2026-08-23 04:04:22 | 5280ms | 2 NS 1 A 4 MX | 🔒 Secure |
| 2026-08-22 03:48:52 | 1158ms | 2 NS 1 A 4 MX | 🔒 Secure |
| 2026-08-11 15:44:12 | 954ms | 2 NS 1 A 4 MX | 🔒 Secure |
| 2026-07-13 06:03:12 | 979ms | 2 NS 1 A 4 MX | 🔒 Secure |
| 2026-07-02 13:48:12 | 9657ms | 2 NS 1 A 4 MX | 🔒 Secure |
| 2026-06-23 21:18:33 shown | 875ms | 2 NS 1 A 4 MX | ⚠️ Bogus |
| 2026-06-22 20:10:12 | 1091ms | 0 NS 0 A 0 MX | ❓ Unknown |
| 2026-06-22 04:12:31 | 631ms | 2 NS 1 A 4 MX | 🔒 Secure |
| 2026-06-16 13:12:40 | 951ms | 2 NS 1 A 4 MX | 🔒 Secure |