Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
rsbk-do.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-04-03 12:14:33 UTC · ↺ Refresh
MX Hostnames
- mx.nrw.schule
MX Priorities
- mx.nrw.schule: 10
A / AAAA Records
- 85.13.151.3 ↩ dd37428.kasserver.com
Mail Server IPs
- 194.77.248.232 ↩ mx.nrw.schule
SOA Record
Raw SOA
ns-soa.dnsmgt.net hostmaster.dokom21.de 2024012553 1800 900 604800 3600
Primary NS (mname)
ns-soa.dnsmgt.net
Admin Email (rname)
hostmaster@dokom21.de
Serial
2024012553
Refresh
1800s
Retry
900s
Expire
604800s
Minimum TTL
3600s
Nameservers (NS)
ns2.dnsmgt.eu
ns1.dnsmgt.net
SPF Record
✓ Strict (-all)
v=spf1 ip4:85.22.150.115 ip4:85.22.150.116 ip4:85.13.151.3 include:_spf.ext.nrw.schule -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none; adkim=r; aspf=r; rua=mailto:[email protected]
⚠ p=none — monitoring only, no enforcement
📋 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 ip4:85.22.150.115 ip4:85.22.150.116 ip4:85.13.151.3 include:_spf.ext.nrw.schule -all
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