Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
cdu-luebben.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-04-04 23:25:12 UTC · ↺ Refresh
MX Hostnames
- mx2.sharkness.de
MX Priorities
- mx2.sharkness.de: 10
A / AAAA Records
- 193.32.223.141 ↩ union3.sharkness.de
Mail Server IPs
- 193.32.223.139 ↩ mx2.sharkness.de
SOA Record
Raw SOA
a.ns14.net support.sharkness.de 2024102500 43200 7200 1209600 86400
Primary NS (mname)
a.ns14.net
Admin Email (rname)
support@sharkness.de
Serial
2024102500
Refresh
43200s
Retry
7200s
Expire
1209600s
Minimum TTL
86400s
Nameservers (NS)
b.ns14.net
c.ns14.net
a.ns14.net
d.ns14.net
SPF Record
✓ Soft Fail (~all)
v=spf1 +a +mx +a:mx1.sharkness.de +a:mx2.sharkness.de +a:mail.sharkness-newsletter.de ~all
📊 DNS lookups: 5/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
⚠ No aggregate reports (rua= not set)
DKIM Selectors
✓ 1 found
default._domainkey
✓ Public key: 216 chars (valid)
✓ DKIM properly configured for selector: default
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
1 record- SPFv=spf1 +a +mx +a:mx1.sharkness.de +a:mx2.sharkness.de +a:mail.sharkness-newsletter.de ~all
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