Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
bolsterlang.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-27 11:53:53 UTC · ↺ Refresh
MX Hostnames
- smtpin.rzone.de
MX Priorities
- smtpin.rzone.de: 5
A / AAAA Records
- 148.251.126.70 ↩ host10.imxnet.de
- 2a01:4f8:210:2145::2 ↩ host10.imxnet.de
Mail Server IPs
- 81.169.145.97 ↩ smtpin.rzone.de
- 2a01:238:20a:202:50f0::1097 ↩ smtpin.rzone.de
SOA Record
Raw SOA
docks01.rzone.de hostmaster.strato-rz.de 2020111026 86400 7200 604800 300
Primary NS (mname)
docks01.rzone.de
Admin Email (rname)
hostmaster@strato-rz.de
Serial
2020111026
Refresh
86400s
Retry
7200s
Expire
604800s
Minimum TTL
300s
Nameservers (NS)
docks01.rzone.de
shades02.rzone.de
SPF Record
✓ Strict (-all)
v=spf1 mx a include:_spf.strato.com include:mail.rechennetz.de -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 a include:_spf.strato.com include:mail.rechennetz.de -all
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