Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
rtz-online.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-28 16:07:38 UTC · ↺ Refresh
MX Hostnames
- mx01.cellitinnen.net
- mx02.cellitinnen.net
MX Priorities
- mx01.cellitinnen.net: 10
- mx02.cellitinnen.net: 20
A / AAAA Records
- 195.82.66.137 ↩ ap137.antwerpes.de
Mail Server IPs
- 87.128.216.153 ↩ mx03.cellitinnen.net
SOA Record
Raw SOA
dns11.netcologne.de hostmaster.netcologne.de 2025070703 28800 7200 604800 3600
Primary NS (mname)
dns11.netcologne.de
Admin Email (rname)
hostmaster@netcologne.de
Serial
2025070703
Refresh
28800s
Retry
7200s
Expire
604800s
Minimum TTL
3600s
Nameservers (NS)
dns13.netcologne.de
dns12.netcologne.de
dns14.netcologne.de
dns11.netcologne.de
SPF Record
✓ Strict (-all)
v=spf1 mx mx:mx01.cellitinnen.net mx:mx02.cellitinnen.net mx:mx03.cellitinnen.net ip4:87.128.216.144/28 ip4:87.79.26.48/28 -all
📊 DNS lookups: 4/10
✓ 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
1 record- SPFv=spf1 mx mx:mx01.cellitinnen.net mx:mx02.cellitinnen.net mx:mx03.cellitinnen.net ip4:87.128.216.144/28 ip4:87.79.26.48/28 -all
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