Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
isf-institut.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-18 20:25:55 UTC · ↺ Refresh
MX Hostnames
- px91.isf-gmbh.com
MX Priorities
- px91.isf-gmbh.com: 10
A / AAAA Records
- 178.63.83.178 ↩ ex44.isf-institut.de
- 2a01:4f8:121:3371::2 ↩ ex44.isf-institut.de
Mail Server IPs
- 136.243.24.67 ↩ px91.isf-gmbh.com
SOA Record
Raw SOA
ns1.first-ns.de dns.hetzner.com 2026031001 86400 10800 360 86400
Primary NS (mname)
ns1.first-ns.de
Admin Email (rname)
dns@hetzner.com
Serial
2026031001
Refresh
86400s
Retry
10800s
Expire
360s
Minimum TTL
86400s
Nameservers (NS)
robotns3.second-ns.com
ns1.first-ns.de
robotns2.second-ns.de
SPF Record
✓ Strict (-all)
v=spf1 mx -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✗ MissingNo DMARC record — emails cannot be rejected on auth failure.
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
4 records- google-site-verification=fK8kuBc0FmndyjljaZrkCUdjUA3EVlEgGld3F4tHEKY
- SPFv=spf1 mx -all
- apple-domain-verification=tSp8e40CPIzJg01p
- google-site-verification=DEVx38vCG3-0PRmqTZb4J4UHkCnsHP6f-SPmzijirRI
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