Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
kontor53.de
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-23 09:44:10 UTC · ↺ Refresh
MX Hostnames
- kontor53-de.mail.protection.outlook.com
MX Priorities
- kontor53-de.mail.protection.outlook.com: 10
A / AAAA Records
- 18.156.188.109 ↩ ec2-18-156-188-109.eu-central-1.compute.amazonaws.com
Mail Server IPs
- 52.101.68.27 ↩ mail-db7pr03cu00503.inbound.protection.outlook.com
- 52.101.68.39 ↩ mail-db7pr03cu00607.inbound.protection.outlook.com
- 52.101.73.22 ↩ mail-am7pr05cu00106.inbound.protection.outlook.com
- 52.101.68.3 ↩ mail-db7pr03cu00403.inbound.protection.outlook.com
- 2a01:111:f403:ca04::1 ↩ mail-db7pr03cu00401.inbound.protection.outlook.com
- 2a01:111:f403:ca04::10 ↩ mail-dbapr03cu00100.inbound.protection.outlook.com
- 2a01:111:f403:ca09::9 ↩ mail-as8pr04cu00801.inbound.protection.outlook.com
- 2a01:111:f403:ca09::8 ↩ mail-as2pr05cu00100.inbound.protection.outlook.com
SOA Record
Raw SOA
hydrogen.ns.hetzner.com dns.hetzner.com 2026020303 86400 10800 3600000 3600
Primary NS (mname)
hydrogen.ns.hetzner.com
Admin Email (rname)
dns@hetzner.com
Serial
2026020303
Refresh
86400s
Retry
10800s
Expire
3600000s
Minimum TTL
3600s
Nameservers (NS)
helium.ns.hetzner.de
hydrogen.ns.hetzner.com
oxygen.ns.hetzner.com
SPF Record
✓ Strict (-all)
v=spf1 a include:spfhoyer.hoyer.de include:spf.protection.outlook.com include:spfhoyermx.hoyer.de -all
📊 DNS lookups: 4/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1;p=quarantine;pct=100;rua=mailto:[email protected];ruf=mailto:[email protected];ri=86400;fo=1;
~ Quarantine — good protection (failing mail goes to spam)
📋 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
3 records- ms-domain-verification=2c3da6ae-d946-4927-b6e3-c655bddde9f2
- SPFv=spf1 a include:spfhoyer.hoyer.de include:spf.protection.outlook.com include:spfhoyermx.hoyer.de -all
- MS=ms48592928
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