rsb.de

Valid Email Server
Domain Lookup › rsb.de

Domain Overview

DNS: ✓ 2mo ago Checker: ✓ 2mo ago
rsb.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Did you mean: [email protected]

Checked via [email protected] · 2026-03-28 22:48:14 UTC · ↺ Refresh

MX Hostnames

  • mx02.hornetsecurity.com
  • mx03.hornetsecurity.com
  • mx01.hornetsecurity.com
  • mx04.hornetsecurity.com

MX Priorities

  • mx01.hornetsecurity.com: 10
  • mx03.hornetsecurity.com: 30
  • mx04.hornetsecurity.com: 40
  • mx02.hornetsecurity.com: 20

A / AAAA Records

  • 185.76.237.144 (no PTR)
  • 2a00:1c98:60:1350::1:fe5:7d88 (no PTR)

Mail Server IPs

  • 94.100.132.8 ↩ mx01.hornetsecurity.com
  • 94.100.134.8 ↩ mx03.hornetsecurity.com
  • 94.100.136.7 ↩ mx04.hornetsecurity.com
  • 94.100.136.8 ↩ mx02.hornetsecurity.com

SOA Record

Raw SOA ns2.knipp.de dnsmaster.irondns.net 17 10800 3000 2419200 900
Primary NS (mname)
ns2.knipp.de
Admin Email (rname)
dnsmaster@irondns.net
Serial
17
Refresh
10800s
Retry
3000s
Expire
2419200s
Minimum TTL
900s

Nameservers (NS)

ns3.knipp.de
ns2.knipp.de
ns17.knipp.net

SPF Record

✓ Strict (-all)
v=spf1 mx ip4:212.144.227.246 ip4:212.144.124.57 ip4:2.207.243.132 ip4:212.144.227.244 include:spf.hornetsecurity.com -all
📊 DNS lookups: 2/10
✓ Hard fail (-all) — strict enforcement

DMARC Record

~ Quarantine
v=DMARC1; p=quarantine; pct=100; adkim=s; aspf=s; rua=mailto:[email protected]
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Strict · DKIM alignment: Strict
📧 Reports → mailto:[email protected]

DKIM Selectors

✗ None detected

No 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

4 records
  • google-site-verification=ru7biEXDM8CyC_Kfrt5a6Tx-b0ouIiM_EdmDQ0JOvqI
  • SPFv=spf1 mx ip4:212.144.227.246 ip4:212.144.124.57 ip4:2.207.243.132 ip4:212.144.227.244 include:spf.hornetsecurity.com -all
  • MS=ms73770117
  • knowbe4-site-verification=653136ace7338f13fb1eaa189dab7df3
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