Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
stz-onlineservice.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-27 11:16:48 UTC · ↺ Refresh
MX Hostnames
- mail.stz-onlineservice.de
MX Priorities
- mail.stz-onlineservice.de: 10
A / AAAA Records
- 45.156.111.39 ↩ node33.securewebsystems.net
Mail Server IPs
- 91.198.228.81 ↩ mail.stz-onlineservice.de
SOA Record
Raw SOA
dns1.securewebsystems.net support.securewebsystems.net 2025102700 21600 3600 1209600 3600
Primary NS (mname)
dns1.securewebsystems.net
Admin Email (rname)
support@securewebsystems.net
Serial
2025102700
Refresh
21600s
Retry
3600s
Expire
1209600s
Minimum TTL
3600s
Nameservers (NS)
dns2.securewebsystems.net
dns1.securewebsystems.net
SPF Record
✓ Strict (-all)
v=spf1 +a +mx +ip4:91.198.228.0/24 +ip4:91.92.232.0/24 +ip4:91.199.247.0/24 +ip4:212.114.86.0/24 include:cemsc.net -all
📊 DNS lookups: 3/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; rua=mailto:[email protected]; ruf=mailto:[email protected]; adkim=r; aspf=r; rf=afrf
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
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 +a +mx +ip4:91.198.228.0/24 +ip4:91.92.232.0/24 +ip4:91.199.247.0/24 +ip4:212.114.86.0/24 include:cemsc.net -all
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