isf.de

Valid Email Server
Domain Lookup › isf.de

Domain Overview

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

Checked via [email protected] · 2026-04-02 16:59:05 UTC · ↺ Refresh

MX Hostnames

  • esa1.itmc.tu-dortmund.de
  • esa2.itmc.tu-dortmund.de

MX Priorities

  • esa1.itmc.tu-dortmund.de: 20
  • esa2.itmc.tu-dortmund.de: 10

A / AAAA Records

  • 195.253.6.139 ↩ http.webredir.bbone.dtm.knipp.de

Mail Server IPs

  • 129.217.131.12 ↩ esa1.itmc.tu-dortmund.de
  • 2001:638:50d:2000::12 ↩ esa1.itmc.tu-dortmund.de
  • 129.217.131.13 ↩ esa2.itmc.tu-dortmund.de
  • 2001:638:50d:2000::13 ↩ esa2.itmc.tu-dortmund.de

SOA Record

Raw SOA ns2.knipp.de dnsmaster.irondns.net 2021081139 10800 3000 2419200 900
Primary NS (mname)
ns2.knipp.de
Admin Email (rname)
dnsmaster@irondns.net
Serial
2021081139
Refresh
10800s
Retry
3000s
Expire
2419200s
Minimum TTL
900s

Nameservers (NS)

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

SPF Record

✗ Missing

No SPF record — domain is unprotected against spoofing.

⚠ No SPF record found. Email servers cannot verify authorized senders.

DMARC Record

✗ Missing

No DMARC record — emails cannot be rejected on auth failure.

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

No TXT records found.

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