cstp.dk is a .dk domain served by 2 nameservers (ns01.one.com, ns02.one.com). It was registered on 29 January 2013 (WHOIS) and was already in the .dk zone when our tracking began on 16 June 2026. Mail is handled by mail.tutanota.de. 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.
| Priority | TTL | Mail Server | IP addresses | PTR | ASN |
|---|---|---|---|---|---|
| 1 | 43200s | mail.tutanota.de | 185.205.69.211 185.205.69.213 185.205.69.214 |
mail.w11.tutanota.de mail.w13.tutanota.de mail.w14.tutanota.de |
AS210909 Tutao GmbH AS210909 Tutao GmbH AS210909 Tutao GmbH |
| TXT Record |
|---|
| t-verify=1a176b337f972bbb69280754f8f57c95 |
| v=spf1 include:spf.tutanota.de -all |
| Policy | Record (cstp.dk) |
|---|---|
| -all (hard fail) | v=spf1 include:spf.tutanota.de -all |
| Policy | Record (_dmarc.cstp.dk) |
|---|---|
| p=quarantine | v=DMARC1; p=quarantine; adkim=s |
| Check | Result |
|---|---|
| Status | 🔒 Enforce |
| TXT record (_mta-sts) | ✓ Found |
| HTTPS policy | ✓ Valid |
| Mode | enforce |
| Policy ID | 20190723 |
| max_age | 86400s |
| Policy MX | mail.tutanota.de |
| www | 46.30.211.38 (AS51468) (address records, no CNAME) |
| www vs bare domain | Only www resolves (all like this) |
| Wildcard | No |
| Denial of existence | NSEC3 · 0 iterations · no salt RFC 9276 ✓ |
| CDS / CDNSKEY | None 0 CDS, 0 CDNSKEY |
| Selector | CNAME | Key |
|---|---|---|
| s1 | s1.domainkey.tutanota.de | RSA · ~2048 bit |
| s2 | s2.domainkey.tutanota.de | 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: 1/10 · policy: -all
No problems found| Service / Owner | Type | Cert association |
|---|---|---|
| SMTP _25._tcp.mail.tutanota.de | DANE-EE · Full cert · SHA-256 | D141F8F3A4AAC2E4D2677AAFCC723D8E… |
| SMTP _25._tcp.mail.tutanota.de | DANE-EE · SPKI · SHA-256 | 5AE0D6DC8A713441003F578C5A1D4D70… |
| Check | Result |
|---|---|
| Validation Status | 🔒 Secure |
| AD Flag (resolver validates) | ✓ Set |
| DS Record | ✓ Found |
| DNSKEY Record | ✓ Found |
| Flags | resolution failed: ncache nxrrset |
| Field | Value |
|---|---|
| Serial | 2026101201 |
| 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 | Punktum dk A/S (direct) |
| Registered | 2013-01-29 |
| Expires | 2027-01-31 (99d) |
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 |
|---|---|---|---|
| 2026-10-23 21:09:03 | 731ms | 2 NS 0 A 1 MX | 🔒 Secure |
| 2026-10-12 18:24:58 shown | 1593ms | 2 NS 0 A 1 MX | 🔒 Secure |
| 2026-10-09 10:22:49 | 749ms | 2 NS 0 A 1 MX | 🔒 Secure |
| 2026-09-30 14:56:10 | 590ms | 2 NS 0 A 1 MX | 🔒 Secure |
| 2026-09-30 08:10:41 | 681ms | 2 NS 0 A 1 MX | 🔒 Secure |
| 2026-09-23 15:36:55 | 679ms | 2 NS 0 A 1 MX | 🔒 Secure |
| 2026-09-11 15:32:23 | 986ms | 2 NS 0 A 1 MX | 🔒 Secure |
| 2026-09-04 13:39:05 | 650ms | 2 NS 0 A 1 MX | 🔒 Secure |
| 2026-08-31 11:26:17 | 750ms | 2 NS 0 A 1 MX | 🔒 Secure |
| 2026-08-25 02:38:32 | 2551ms | 2 NS 0 A 1 MX | 🔒 Secure |
| 2026-08-12 18:40:58 | 3087ms | 2 NS 0 A 1 MX | 🔒 Secure |
| 2026-07-19 00:47:46 | 862ms | 2 NS 0 A 1 MX | 🔒 Secure |
| 2026-07-13 14:06:48 | 994ms | 2 NS 0 A 1 MX | 🔒 Secure |
| 2026-06-22 05:44:43 | 799ms | 2 NS 0 A 1 MX | 🔒 Secure |
| 2026-06-16 23:06:01 | 707ms | 2 NS 0 A 1 MX | ⚠️ Bogus |