holckenhavn.dk is a .dk domain served by 2 nameservers (adel.ns.cloudflare.com, aiden.ns.cloudflare.com). It was registered on 8 October 1999 (WHOIS) and was already in the .dk zone when our tracking began on 16 June 2026. Its website address 104.21.15.71 is hosted by Cloudflare, Inc. (AS13335). Mail is handled by holckenhavn-dk.mail.protection.outlook.com. The zone is not DNSSEC-signed, publishes a DMARC policy and is reachable over IPv6. Below are all of its DNS records from our latest 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 |
|---|---|---|---|---|---|---|---|
| 104.21.15.71 | 300s | — | AS13335 | Cloudflare, Inc. | 104.21.0.0/17 | — | — |
| 172.67.161.235 | 300s | — | AS13335 | Cloudflare, Inc. | 172.67.128.0/17 | — | — |
| Service | CNAME / IP |
|---|---|
| 🔷 Autodiscover | autodiscover.outlook.com → 52.98.149.152 |
| IPv6 Address | TTL | PTR | ASN | ISP / Org | CIDR | Country | City |
|---|---|---|---|---|---|---|---|
| 2606:4700:3033::ac43:a1eb | 300s | — | AS13335 | Cloudflare, Inc. | 2606:4700:3000:0:0:0:0:0/42 | — | — |
| 2606:4700:3037::6815:f47 | 300s | — | AS13335 | Cloudflare, Inc. | 2606:4700:3000:0:0:0:0:0/42 | — | — |
| Priority | Target | SvcParams |
|---|---|---|
| 1 service | . | alpn="h3,h2" ipv4hint=104.21.15.71,172.67.161.235 ech=AEX+DQBBwwAgACBWsgAkONUSzcIOieAd82NhsPUyOjw0lnuJR7KZyKStDAAEAAEAAQASY2xvdWRmbGFyZS1lY2guY29tAAA= ipv6hint=2606:4700:3033::ac43:a1eb,2606:4700:3037::6815:f47 |
| Service | Priority | Weight | Port | Target |
|---|---|---|---|---|
| _sipfederationtls._tcp | 100 | 1 | 5061 | sipfed.online.lync.com |
| TXT Record |
|---|
| MS=ms31180906 |
| v=spf1 mx a a:mail.holckenhavn.dk a:fw01.holckenhavn.dk include:spf.protection.outlook.com include:amazonses.com -all |
| Policy | Record (holckenhavn.dk) |
|---|---|
| -all (hard fail) | v=spf1 mx a a:mail.holckenhavn.dk a:fw01.holckenhavn.dk include:spf.protection.outlook.com include:amazonses.com -all |
| Policy | Record (_dmarc.holckenhavn.dk) |
|---|---|
| p=reject | v=DMARC1; p=reject; fo=1; pct=100 |
| www | 104.21.15.71 172.67.161.235 2606:4700:3033::ac43:a1eb 2606:4700:3037::6815:f47 (AS13335) (address records, no CNAME) |
| www vs bare domain | Same network holckenhavn.dk: 104.21.15.71 172.67.161.235 2606:4700:3033::ac43:a1eb 2606:4700:3037::6815:f47 (AS13335) www.holckenhavn.dk: 104.21.15.71 172.67.161.235 2606:4700:3033::ac43:a1eb 2606:4700:3037::6815:f47 (AS13335) |
| Wildcard | No |
| Selector | CNAME | Key |
|---|---|---|
| dkim | — | RSA · ~1024 bit below 2048 bit test mode |
| s1 | s1.domainkey.u3979832.wl083.sendgrid.net | RSA · ~2048 bit |
| s2 | s2.domainkey.u3979832.wl083.sendgrid.net | RSA · ~1024 bit below 2048 bit |
| selector1 | selector1-holckenhavn-dk._domainkey.holckenhavn.onmicrosoft.com | RSA · ~1024 bit below 2048 bit |
| selector2 | selector2-holckenhavn-dk._domainkey.holckenhavn.onmicrosoft.com | RSA · ~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: 6/10 · policy: -all
No problems found| 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 | 2416078398 |
| Primary NS (MNAME) | adel.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 | 1999-10-08 |
| Expires | 2026-12-31 (68d) |
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 |
|---|---|---|---|
| 2026-10-22 00:54:26 shown | 1172ms | 2 NS 2 A 1 MX | 🔓 Insecure |
| 2026-09-28 19:04:25 | 1473ms | 2 NS 2 A 1 MX | 🔓 Insecure |
| 2026-09-24 18:12:33 | 939ms | 2 NS 2 A 1 MX | 🔓 Insecure |
| 2026-08-30 17:14:11 | 937ms | 2 NS 2 A 1 MX | 🔓 Insecure |
| 2026-08-28 21:12:50 | 1656ms | 2 NS 2 A 1 MX | 🔓 Insecure |
| 2026-08-01 08:21:44 | 1539ms | 2 NS 2 A 1 MX | 🔓 Insecure |
| 2026-06-28 08:04:33 | 2576ms | 2 NS 2 A 1 MX | 🔓 Insecure |
| 2026-06-25 22:51:01 | 2310ms | 2 NS 2 A 1 MX | 🔓 Insecure |
| 2026-06-25 05:02:39 | 1608ms | 2 NS 2 A 1 MX | 🔓 Insecure |
| 2026-06-25 03:58:26 | 3060ms | 2 NS 2 A 1 MX | 🔓 Insecure |
| 2026-06-20 02:53:16 | 2840ms | 2 NS 2 A 1 MX | 🔓 Insecure |
| 2026-06-18 22:06:05 | 3872ms | 2 NS 2 A 1 MX | 🔓 Insecure |
| 2026-06-17 13:16:34 | 271ms | 0 NS 0 A 0 MX | ❓ Unknown |