Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
sis-institut.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-04-03 17:43:42 UTC · ↺ Refresh
MX Hostnames
- pop2.osmailserver.de
MX Priorities
- pop2.osmailserver.de: 10
A / AAAA Records
- 85.10.251.102 ↩ 85-10-251-102.clients.your-server.de
Mail Server IPs
- 85.10.251.18 ↩ pop2.osmailserver.de
SOA Record
Raw SOA
ns1.first-ns.de dns.hetzner.com 2025111400 14400 1800 604800 86400
Primary NS (mname)
ns1.first-ns.de
Admin Email (rname)
dns@hetzner.com
Serial
2025111400
Refresh
14400s
Retry
1800s
Expire
604800s
Minimum TTL
86400s
Nameservers (NS)
robotns3.second-ns.com
ns1.first-ns.de
robotns2.second-ns.de
SPF Record
✓ Strict (-all)
v=spf1 +mx include:spf.mailjet.com a:smtp2.osmailserver.de a:smtp.osmailserver.de a:smtp3.osmailserver.de include:spf.server-he.de -all
📊 DNS lookups: 6/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; rua=mailto:[email protected];
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✗ None detectedNo DKIM records found for common selectors — your provider may use a custom selector name.
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
1 record- SPFv=spf1 +mx include:spf.mailjet.com a:smtp2.osmailserver.de a:smtp.osmailserver.de a:smtp3.osmailserver.de include:spf.server-he.de -all
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