esbu.dk is a .dk domain served by 2 nameservers (brit.ns.cloudflare.com, mack.ns.cloudflare.com). It was registered on 26 November 2001 (WHOIS) and was already in the .dk zone when our tracking began on 16 June 2026. Its website address 185.21.40.55 is hosted by team.blue Denmark A/S (AS48854) in Denmark. 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.
| Nameserver | IP addresses | PTR | ASN / ISP |
|---|---|---|---|
| brit.ns.cloudflare.com | — | — | — |
| mack.ns.cloudflare.com | — | — | — |
| IP | TTL | PTR | ASN | ISP / Org | CIDR | Country | City |
|---|---|---|---|---|---|---|---|
| 185.21.40.55 | — | vm1251.enterprisecloud.nu | AS48854 | team.blue Denmark A/S | 185.21.40.0/22 | 🇩🇰 Denmark | — |
| TXT Record |
|---|
| v=spf1 -all |
| Policy | Record (esbu.dk) |
|---|---|
| -all (hard fail) | v=spf1 -all |
| Policy | Record (_dmarc.esbu.dk) |
|---|---|
| p=reject | v=DMARC1; p=reject; sp=reject; adkim=s; aspf=s; |
| www CNAME | esbu.dk (all on esbu.dk) → 185.21.40.55 (AS48854) |
| www vs bare domain | Same network |
| Wildcard | No |
| Denial of existence | Compact NSEC (RFC 9824, "black lies") not walkable |
| CDS / CDNSKEY | Published: key rollovers can be automated with the registry (RFC 7344/8078) 1 CDS, 1 CDNSKEY |
DNS lookups: 0/10 · 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 | 2407098304 |
| Primary NS (MNAME) | brit.ns.cloudflare.com |
| Responsible (RNAME) | dns@cloudflare.com |
| Refresh | 10000s |
| Retry | 2400s |
| Expire | 604800s |
| Minimum (neg-cache TTL) | 1800s |
| Field | Value |
|---|---|
| Registrar | DANDOMAIN A/S |
| Registered | 2001-11-26 |
| Expires | 2026-12-31 (74d) |
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).
| Scanned At | Duration | Records | DNSSEC |
|---|---|---|---|
| 2026-10-15 04:43:27 | 1451ms | 2 NS 1 A 0 MX | 🔒 Secure |
| 2026-09-26 06:02:21 | 524ms | 2 NS 1 A 0 MX | 🔒 Secure |
| 2026-09-25 07:27:45 | 518ms | 2 NS 1 A 0 MX | 🔒 Secure |
| 2026-09-24 07:24:26 | 533ms | 2 NS 1 A 0 MX | 🔒 Secure |
| 2026-09-22 10:18:12 | 911ms | 2 NS 1 A 0 MX | 🔒 Secure |
| 2026-08-28 15:51:00 | 2553ms | 2 NS 1 A 0 MX | 🔒 Secure |
| 2026-08-14 02:49:50 | 3573ms | 2 NS 1 A 0 MX | 🔒 Secure |
| 2026-08-06 21:04:38 | 930ms | 2 NS 1 A 0 MX | 🔒 Secure |
| 2026-07-26 09:05:03 | 8943ms | 2 NS 1 A 0 MX | 🔒 Secure |
| 2026-07-24 08:08:43 | 839ms | 2 NS 1 A 0 MX | 🔒 Secure |
| 2026-07-10 15:38:07 | 1027ms | 2 NS 1 A 0 MX | 🔒 Secure |
| 2026-06-23 04:31:00 | 830ms | 2 NS 1 A 0 MX | 🔒 Secure |
| 2026-06-20 04:15:19 | 436ms | 2 NS 1 A 0 MX | 🔒 Secure |
| 2026-06-17 08:20:16 shown | 366ms | 2 NS 1 A 0 MX | 🔒 Secure |
| 2026-06-17 08:20:11 | 430ms | 2 NS 1 A 0 MX | 🔒 Secure |