Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
koestner.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-21 12:42:51 UTC · ↺ Refresh
MX Hostnames
- mail.koestner.de
MX Priorities
- mail.koestner.de: 10
A / AAAA Records
- 185.181.133.59 ↩ r30174.agenturserver.it
Mail Server IPs
- 80.150.64.188 ↩ mail.koestner.de
SOA Record
Raw SOA
ns1.telekom-domains.de dns.telekom.de 2025112101 10800 3600 2419200 43200
Primary NS (mname)
ns1.telekom-domains.de
Admin Email (rname)
dns@telekom.de
Serial
2025112101
Refresh
10800s
Retry
3600s
Expire
2419200s
Minimum TTL
43200s
Nameservers (NS)
ns2.telekom-domains.de
ns1.telekom-domains.de
SPF Record
✓ Strict (-all)
v=spf1 mx ip4:185.158.212.237 -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1;p=quarantine;ruf=mailto:[email protected]
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
⚠ No aggregate reports (rua= not set)
DKIM Selectors
✓ 1 found
s1._domainkey
✓ Public key: 392 chars (valid)
✓ DKIM properly configured for selector: s1
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
7 records- logmein-verification-code=ed0dfc86-0876-44bc-bc52-c0b7b661245e
- google-gws-recovery-domain-verification=39250032
- apple-domain-verification=uXh1g6U9SRt5fnrK
- cisco-ci-domain-verification=4612cc465f0bf07f7743cab282c7ee81c66a3b8b169c1712dc5c952cc262cad6
- placetel-domain-verification=z5TywkcbvLLxZwiCwBiCTmlyA_5Xqayh69N-nEIggYY
- MS=6875BC7D4D8121DB2D2A1C2F4A422BC5F003577E
- SPFv=spf1 mx ip4:185.158.212.237 -all
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