Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
holger-clasen.de
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-19 00:47:57 UTC · ↺ Refresh
MX Hostnames
- holgerclasen-de01e.mail.protection.outlook.com
MX Priorities
- holgerclasen-de01e.mail.protection.outlook.com: 1
A / AAAA Records
- 142.132.209.244 ↩ hserv7.ctnm.de
Mail Server IPs
- 52.101.68.27 ↩ mail-db7pr03cu00503.inbound.protection.outlook.com
- 52.101.73.19 ↩ mail-as8pr04cu00803.inbound.protection.outlook.com
- 52.101.73.30 ↩ mail-am7pr05cu00306.inbound.protection.outlook.com
- 52.101.73.1 ↩ mail-am3pr04cu00501.inbound.protection.outlook.com
- 2a01:111:f403:ca04:: ↩ mail-db3pr0202cu00100.inbound.protection.outlook.com
- 2a01:111:f403:ca09::f ↩ mail-am7pr05cu00307.inbound.protection.outlook.com
- 2a01:111:f403:ca09::4 ↩ mail-am0pr04cu00504.inbound.protection.outlook.com
- 2a01:111:f403:ca04::9 ↩ mail-db7pr03cu00601.inbound.protection.outlook.com
SOA Record
Raw SOA
ns1072.ui-dns.de hostmaster.schlund.de 2017042354 28800 7200 604800 300
Primary NS (mname)
ns1072.ui-dns.de
Admin Email (rname)
hostmaster@schlund.de
Serial
2017042354
Refresh
28800s
Retry
7200s
Expire
604800s
Minimum TTL
300s
Nameservers (NS)
ns1072.ui-dns.com
ns1072.ui-dns.biz
ns1072.ui-dns.org
ns1072.ui-dns.de
SPF Record
✓ Soft Fail (~all)
v=spf1 include:spf.protection.outlook.com a a:sambus-web01.nmmn.com include:_spf-eu.ionos.com mx:remote.holger-clasen.de ip4:217.114.64.179 ip4:157.97.111.233 ip4:212.127.50.93 ~all
📊 DNS lookups: 5/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; rua=mailto:[email protected]; ruf=mailto:[email protected]
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 2 found
selector1._domainkey
selector2._domainkey
✓ Public key: 392 chars (valid)
✓ DKIM properly configured for selector: selector1
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
7 records- MS=ms40015677
- SPFv=spf1 include:spf.protection.outlook.com a a:sambus-web01.nmmn.com include:_spf-eu.ionos.com mx:remote.holger-clasen.de ip4:217.114.64.179 ip4:157.97.111.233 ip4:212.127.50.93 ~all
- i3lfonmir4ilofi2t2ohe997ad
- v=verifydomain MS=7060767
- google-site-verification=CpQPeigvag7z2HFHeT6pLWDeUzFq_Vwbe1IGBeETUeU
- PbX0V7PgZmuFWYKSFGfa
- apple-domain-verification=6ovsYwkK6-QLMTQ8mUHObPt1Xl0vK9nFP24HFI0bdho
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