Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
guerstergmbh.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-25 13:01:20 UTC · ↺ Refresh
MX Hostnames
- mx-a.secumail.de
- mx-b.secumail.de
MX Priorities
- mx-a.secumail.de: 10
- mx-b.secumail.de: 20
A / AAAA Records
- 62.146.186.129 ↩ 186-129-server.nbg.cyberstack.de
Mail Server IPs
- 212.11.225.17 ↩ sc03.secumail.de
- 212.11.225.133 ↩ sc01.secumail.de
- 212.11.224.132 ↩ sc02.secumail.de
- 212.11.224.154 ↩ sc04.secumail.de
SOA Record
Raw SOA
dns.cyber-stack.de hostmaster.cyberstack.de 2024010802 10800 1800 2592000 40000
Primary NS (mname)
dns.cyber-stack.de
Admin Email (rname)
hostmaster@cyberstack.de
Serial
2024010802
Refresh
10800s
Retry
1800s
Expire
2592000s
Minimum TTL
40000s
Nameservers (NS)
dns.cyber-stack.de
dns.cyber-stack.com
SPF Record
✓ Strict (-all)
v=spf1 include:spf.mailfusion.de include:spf.protection.outlook.com mx -all
📊 DNS lookups: 3/10
✓ 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
2 records- MS=ms63835761
- SPFv=spf1 include:spf.mailfusion.de include:spf.protection.outlook.com mx -all
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