Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
kosads.nl
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-17 22:56:00 UTC · ↺ Refresh
MX Hostnames
- smtp.rzone.de
MX Priorities
- smtp.rzone.de: 5
A / AAAA Records
- 217.160.0.219 ↩ 217-160-0-219.elastic-ssl.ui-r.com
- 2001:8d8:100f:f000::200 ↩ 2001-08d8-100f-f000-0000-0000-0000-0200.elastic-ssl.ui-r.com
Mail Server IPs
- 81.169.145.98 ↩ smtp.rzone.de
- 2a01:238:20a:202:50f0::2097 ↩ smtp.rzone.de
SOA Record
Raw SOA
docks13.rzone.de hostmaster.strato-rz.de 2023040221 86400 7200 604800 300
Primary NS (mname)
docks13.rzone.de
Admin Email (rname)
hostmaster@strato-rz.de
Serial
2023040221
Refresh
86400s
Retry
7200s
Expire
604800s
Minimum TTL
300s
Nameservers (NS)
docks13.rzone.de
shades17.rzone.de
SPF Record
✓ Soft Fail (~all)
v=spf1 redirect=_spf.strato.com
📊 DNS lookups: 1/10
DMARC Record
~ Quarantine
v=DMARC1; p=quarantine; pct=100
~ 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: 216 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
1 record- SPFv=spf1 redirect=_spf.strato.com
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