josekoster.nl

Valid Email Server
Domain Lookup › josekoster.nl

Domain Overview

DNS: ✓ 2mo ago Checker: ✓ 2mo ago
josekoster.nl
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No

Checked via [email protected] · 2026-03-14 08:12:41 UTC · ↺ Refresh

MX Hostnames

  • mail.josekoster.nl

MX Priorities

  • mail.josekoster.nl: 10

A / AAAA Records

  • 213.154.231.201 ↩ web0101.theory7.net
  • 2001:7b8:618:a:213:154:231:201 ↩ web0101.theory7.net

Mail Server IPs

  • 213.154.231.201 ↩ web0101.theory7.net
  • 2001:7b8:618:a:213:154:231:201 ↩ web0101.theory7.net

SOA Record

Raw SOA ns.theory7.net hostmaster.josekoster.nl 2026012832 3600 3600 1209600 86400
Primary NS (mname)
ns.theory7.net
Admin Email (rname)
hostmaster@josekoster.nl
Serial
2026012832
Refresh
3600s
Retry
3600s
Expire
1209600s
Minimum TTL
86400s

Nameservers (NS)

ns.theory7.nl
ns.theory7.eu
ns.theory7.net

SPF Record

✓ Strict (-all)
v=spf1 a mx ip4:213.154.231.201 include:filter.theory7.net ip6:2001:7b8:618:a:213:154:231:201 -all
📊 DNS lookups: 4/10
✓ Hard fail (-all) — strict enforcement

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

1 record
  • SPFv=spf1 a mx ip4:213.154.231.201 include:filter.theory7.net ip6:2001:7b8:618:a:213:154:231:201 -all
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