Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
mainz-online.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-30 20:40:02 UTC · ↺ Refresh
MX Hostnames
- mx-a.ktk.de
- mx-b.ktk.de
MX Priorities
- mx-b.ktk.de: 30
- mx-a.ktk.de: 30
A / AAAA Records
- 185.132.224.41 (no PTR)
Mail Server IPs
- 82.115.96.243 ↩ mx-b.ktk.de
- 2a02:1628::c004:0:0:0:243 ↩ mx-b.ktk.de
- 82.115.96.242 ↩ mx-a.ktk.de
- 2a02:1628::c004:0:0:0:242 ↩ mx-a.ktk.de
SOA Record
Raw SOA
ns-a.ktk.de hostmaster.noc.ktk.de 2019052102 3600 900 604800 3600
Primary NS (mname)
ns-a.ktk.de
Admin Email (rname)
hostmaster@noc.ktk.de
Serial
2019052102
Refresh
3600s
Retry
900s
Expire
604800s
Minimum TTL
3600s
Nameservers (NS)
ns-b.ktk.io
ns-a.ktk.de
ns-c.ktk.de
SPF Record
✓ Soft Fail (~all)
v=spf1 include:mail.ktk.de ~all
📊 DNS lookups: 1/10
~ Soft fail (~all) — moderate 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
1 record- SPFv=spf1 include:mail.ktk.de ~all
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