c2u.dk is a .dk domain served by 2 nameservers (eric.ns.cloudflare.com, nena.ns.cloudflare.com). It was registered on 26 June 2006 (WHOIS) and was already in the .dk zone when our tracking began on 16 June 2026. Its website address 104.21.87.216 is hosted by Cloudflare, Inc. (AS13335). Mail is handled by aspmx.l.google.com, alt1.aspmx.l.google.com and 3 more. The zone is not DNSSEC-signed, publishes a DMARC policy and is reachable over IPv6. 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 |
|---|---|---|---|---|---|---|---|
| 104.21.87.216 | 300s | — | AS13335 | Cloudflare, Inc. | 104.21.0.0/17 | — | — |
| 172.67.147.2 | 300s | — | AS13335 | Cloudflare, Inc. | 172.67.128.0/17 | — | — |
| IPv6 Address | TTL | PTR | ASN | ISP / Org | CIDR | Country | City |
|---|---|---|---|---|---|---|---|
| 2606:4700:3031::6815:57d8 | 300s | — | AS13335 | Cloudflare, Inc. | 2606:4700:3000:0:0:0:0:0/42 | — | — |
| 2606:4700:3033::ac43:9302 | 300s | — | AS13335 | Cloudflare, Inc. | 2606:4700:3000:0:0:0:0:0/42 | — | — |
| Priority | Target | SvcParams |
|---|---|---|
| 1 service | . | alpn="h3,h2" ipv4hint=104.21.87.216,172.67.147.2 ech=AEX+DQBBjgAgACAGd+wmoXQPMjzXpkwY+ze8vrvyh3X6bHrF0BXN0GD2OwAEAAEAAQASY2xvdWRmbGFyZS1lY2guY29tAAA= ipv6hint=2606:4700:3031::6815:57d8,2606:4700:3033::ac43:9302 |
| TXT Record |
|---|
| google-site-verification=HWfM0QzliDLntljIxacHEzU3xz8Q7IkfVmD8s-3ovAg |
| v=spf1 include:spf.surf-down.net include:_spf.google.com ~all |
| Policy | Record (c2u.dk) |
|---|---|
| ~all (soft fail) | v=spf1 include:spf.surf-down.net include:_spf.google.com ~all |
| Policy | Record (_dmarc.c2u.dk) |
|---|---|
| p=none (monitor only) | v=DMARC1; p=none; rua=mailto:913f537e5cd6344@rep.dmarcanalyzer.com; sp=none; |
| www | 104.21.87.216 172.67.147.2 2606:4700:3031::6815:57d8 2606:4700:3033::ac43:9302 (AS13335) (address records, no CNAME) |
| www vs bare domain | Same network |
| Wildcard | No |
DNS lookups: 2/10 · policy: ~all
| Type | Name | Value |
|---|---|---|
| TXT | _acme-challenge.c2u.dk | G2KgAyUGWitbCK-AES-P_lNmHfbWhX7Tgu2yXrWsQ24 |
| TXT | _acme-challenge.c2u.dk | Ld_UmtNhwaG4-LJFGjyUMVnzys6z1BKbWiSFimG6lMM |
| Check | Result |
|---|---|
| Validation Status | 🔓 Insecure |
| AD Flag (resolver validates) | ✗ Not set |
| DS Record | ✗ Not found |
| DNSKEY Record | ✗ Not found |
| Flags | unsigned answer |
| Field | Value |
|---|---|
| Serial | 2412421842 |
| Primary NS (MNAME) | eric.ns.cloudflare.com |
| Responsible (RNAME) | dns@cloudflare.com |
| Refresh | 10000s |
| Retry | 2400s |
| Expire | 604800s |
| Minimum (neg-cache TTL) | 1800s |
| Field | Value |
|---|---|
| Registrar | Punktum dk A/S (direct) |
| Registered | 2006-06-26 |
| Expires | 2027-06-30 (255d) |
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 |
|---|---|---|---|
| 2026-10-08 15:25:06 | 649ms | 2 NS 2 A 5 MX | 🔓 Insecure |
| 2026-09-30 03:47:19 | 2597ms | 2 NS 2 A 5 MX | 🔓 Insecure |
| 2026-09-27 09:30:56 | 1332ms | 2 NS 2 A 5 MX | 🔓 Insecure |
| 2026-09-07 06:14:16 | 9685ms | 2 NS 2 A 5 MX | 🔓 Insecure |
| 2026-08-26 11:23:59 | 1465ms | 2 NS 2 A 5 MX | 🔓 Insecure |
| 2026-08-18 21:27:17 | 9462ms | 2 NS 2 A 5 MX | 🔓 Insecure |
| 2026-08-17 13:41:48 shown | 3269ms | 2 NS 2 A 5 MX | 🔓 Insecure |
| 2026-06-27 11:30:10 | 2451ms | 2 NS 2 A 5 MX | 🔓 Insecure |
| 2026-06-27 07:15:48 | 1009ms | 2 NS 2 A 5 MX | 🔓 Insecure |
| 2026-06-19 18:54:48 | 991ms | 2 NS 2 A 5 MX | 🔓 Insecure |
| 2026-06-16 18:45:35 | 534ms | 2 NS 2 A 5 MX | 🔓 Insecure |
| 2026-06-16 18:40:34 | 723ms | 2 NS 2 A 5 MX | 🔓 Insecure |