altero.dk is a .dk domain served by 2 nameservers (ns1.123hotel.dk, ns2.123hotel.dk). It was already in the .dk zone when our tracking began on 16 June 2026. Its website address 185.21.40.141 is hosted by team.blue Denmark A/S (AS48854) in Denmark. Mail is handled by mx.spamfilter.io. 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 |
|---|---|---|---|---|---|---|---|
| 185.21.40.141 | 3600s | web133.123hotel.dk | AS48854 | team.blue Denmark A/S | 185.21.40.0/22 | 🇩🇰 Denmark | — |
| Service | CNAME / IP |
|---|---|
| 🔷 Autodiscover | autodiscover-mf.onlinemail.io → 185.21.40.62 |
| 🔶 Autoconfig | autoconfig-mf.onlinemail.io → 185.21.40.62 |
| TXT Record |
|---|
| google-site-verification=KVz62m3IwgpUYCDAdsm8ot9VNa7GOnklQwZod5gOvYA |
| v=spf1 a include:spf.curanet.dk include:spf.spamfilter.io include:mailgun.org ~all |
| Policy | Record (altero.dk) |
|---|---|
| ~all (soft fail) | v=spf1 a include:spf.curanet.dk include:spf.spamfilter.io include:mailgun.org ~all |
| Policy | Record (_dmarc.altero.dk) |
|---|---|
| p=reject | v=DMARC1; p=reject; rua=mailto:dmarc@altero.dk; ruf=mailto:dmarc@altero.dk; pct=100; fo=s; |
| www | 185.21.40.141 (AS48854) (address records, no CNAME) |
| www vs bare domain | Same network |
| Wildcard | No |
| Denial of existence | NSEC3 · 1 iteration · 1-byte salt RFC 9276 recommends 0 iterations and no salt |
| CDS / CDNSKEY | None 0 CDS, 0 CDNSKEY |
| Selector | CNAME | Key |
|---|---|---|
| s1 | — | 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: 10/10 · policy: ~all
| Service / Owner | Type | Cert association |
|---|---|---|
| SMTP _25._tcp.mx.spamfilter.io | DANE-EE · SPKI · SHA-256 | 9A25F05F2E322DABDCC9B7A06AB47A2D… |
| Check | Result |
|---|---|
| Validation Status | 🔒 Secure |
| AD Flag (resolver validates) | ✓ Set |
| DS Record | ✓ Found |
| DNSKEY Record | ✓ Found |
| Flags | fully validated |
| Field | Value |
|---|---|
| Serial | 2025091701 |
| Primary NS (MNAME) | ns1.123hotel.dk |
| Responsible (RNAME) | hostmaster@curanet.dk |
| Refresh | 14400s |
| Retry | 3600s |
| Expire | 1209600s |
| Minimum (neg-cache TTL) | 300s |
| Scanned At | Duration | Records | DNSSEC |
|---|---|---|---|
| 2026-09-30 14:51:17 | 963ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-09-10 09:05:57 shown | 527ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-09-04 03:35:38 | 516ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-06-28 11:46:30 | 1795ms | 2 NS 1 A 1 MX | 🔒 Secure |
| 2026-06-16 13:24:32 | 2637ms | 2 NS 1 A 1 MX | 🔒 Secure |