Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
ctb.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-26 03:59:10 UTC · ↺ Refresh
MX Hostnames
- mx01.ionos.de
- mx00.ionos.de
MX Priorities
- mx01.ionos.de: 10
- mx00.ionos.de: 10
A / AAAA Records
- 217.160.0.140 ↩ 217-160-0-140.elastic-ssl.ui-r.com
Mail Server IPs
- 217.72.192.67 ↩ mx01.kundenserver.de
- 212.227.15.41 ↩ mx00.kundenserver.de
SOA Record
Raw SOA
ns55.kundenserver.de hostmaster.kundenserver.de 2017030251 28800 7200 604800 300
Primary NS (mname)
ns55.kundenserver.de
Admin Email (rname)
hostmaster@kundenserver.de
Serial
2017030251
Refresh
28800s
Retry
7200s
Expire
604800s
Minimum TTL
300s
Nameservers (NS)
ns56.kundenserver.de
ns55.kundenserver.de
SPF Record
✓ Soft Fail (~all)
v=spf1 include:_spf.perfora.net include:_spf-eu.ionos.com include:_spf.kundenserver.de ~all
📊 DNS lookups: 3/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
✗ p=none
v=DMARC1;p=none;pct=100;rua=mailto:[email protected]
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 1 found
mail._domainkey
✓ Public key: 216 chars (valid)
✓ DKIM properly configured for selector: mail
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
2 records- SPFv=spf1 include:_spf.perfora.net include:_spf-eu.ionos.com include:_spf.kundenserver.de ~all
- brevo-code:3e407b5ba78599553adb70c26ce45d86
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