cmk.dk is a .dk domain served by 2 nameservers (ns01.one.com, ns02.one.com). It was registered on 5 October 2025 (WHOIS) and was already in the .dk zone when our tracking began on 16 June 2026. Its website address 176.21.113.227 is hosted by TDC Holding A/S (AS3292) in Denmark. Mail is handled by cmk.dk. The zone is DNSSEC-signed and validates, publishes a 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 |
|---|---|---|---|---|---|---|---|
| 176.21.113.227 | 3600s | 176-21-113-227-cable.dk.customer.tdc.net | AS3292 | TDC Holding A/S | 176.21.0.0/16 | 🇩🇰 Denmark | Copenhagen |
| Priority | TTL | Mail Server | IP addresses | PTR | ASN |
|---|---|---|---|---|---|
| 10 | 3600s | cmk.dk | 176.21.113.227 | 176-21-113-227-cable.dk.customer.tdc.net | AS3292 TDC Holding A/S |
| Service | CNAME / IP |
|---|---|
| 🔷 Autodiscover | 176.21.113.227 |
| 🔶 Autoconfig | 176.21.113.227 |
| TXT Record |
|---|
| v=spf1 a mx -all |
| Policy | Record (cmk.dk) |
|---|---|
| -all (hard fail) | v=spf1 a mx -all |
| Policy | Record (_dmarc.cmk.dk) |
|---|---|
| p=quarantine | v=DMARC1; p=quarantine; pct=100; rua=mailto:postmaster@klestrup.com |
| Flags | Tag | Value |
|---|---|---|
| 0 | issue | letsencrypt.org |
| www | 176.21.113.227 (AS3292) (address records, no CNAME) |
| www vs bare domain | Same network |
| Wildcard | Yes: any name under the zone resolves |
| CDS / CDNSKEY | None 0 CDS, 0 CDNSKEY |
| Selector | CNAME | Key |
|---|---|---|
| default | — | RSA · ~1024 bit below 2048 bit |
| — | RSA · ~1024 bit below 2048 bit |
DKIM selectors can't be listed, so we check the common ones (Microsoft 365, Google, Mailchimp, SendGrid, generic). Keys under other selectors aren't shown.
DNS lookups: 2/10 · policy: -all
No problems found| Check | Result |
|---|---|
| Validation Status | 🔒 Secure |
| AD Flag (resolver validates) | ✓ Set |
| DS Record | ✓ Found |
| DNSKEY Record | ✓ Found |
| Flags | fully validated |
| Field | Value |
|---|---|
| Serial | 2026072901 |
| 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 | 2025-10-05 |
| Expires | 2027-10-04 (349d) |
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).
| Domain | Registrar |
|---|---|
| susannesmusikskole.dk | ONE.COM A/S |
| Scanned At | Duration | Records | DNSSEC |
|---|---|---|---|
| 2026-09-30 14:32:07 | 452ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-09-29 17:48:03 | 704ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-09-29 11:12:46 | 564ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-09-25 10:44:49 | 715ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-09-24 12:29:53 | 663ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-09-17 21:07:07 | 515ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-09-03 07:01:14 | 1524ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-08-30 01:22:22 | 1216ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-08-20 17:17:57 | 714ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-08-06 18:54:14 shown | 893ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-06-29 07:54:19 | 568ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-06-23 15:06:03 | 2929ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-06-20 16:39:02 | 1188ms | 0 NS 0 A 0 MX | ❓ Unknown |
| 2026-06-20 00:01:22 | 713ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-06-16 21:50:22 | 60617ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-06-16 21:36:41 | 1583ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-06-16 21:30:39 | 496ms | 2 NS 1 A 1 MX | 🔒 Secure |