Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
felix-klein-zentrum.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-04-03 08:31:05 UTC · ↺ Refresh
MX Hostnames
- mail.joker.com
MX Priorities
- mail.joker.com: 10
A / AAAA Records
- 192.102.162.236 ↩ 192-102-162-236.vm.c.fraunhofer.de
Mail Server IPs
- 194.245.148.6 ↩ mailfw3.joker-forward.com
- 194.245.148.9 ↩ mailfw4.joker-forward.com
SOA Record
Raw SOA
x.ns.joker.com hostmaster.joker.com 2025121550 14400 3600 604800 300
Primary NS (mname)
x.ns.joker.com
Admin Email (rname)
hostmaster@joker.com
Serial
2025121550
Refresh
14400s
Retry
3600s
Expire
604800s
Minimum TTL
300s
Nameservers (NS)
x.ns.joker.com
y.ns.joker.com
z.ns.joker.com
SPF Record
✗ Invalid
v=spf1 -all
📊 DNS lookups: 0/10
⚠ Strict -all with no allowed senders — no servers can send email for this domain.
DMARC Record
✓ Reject
v=DMARC1; p=reject; sp=reject; adkim=s; aspf=s;
✓ Reject — strongest protection
📋 SPF alignment: Strict
· DKIM alignment: Strict
⚠ No aggregate reports (rua= not set)
↳ Subdomain policy: reject
DKIM Selectors
✓ 13 found
google._domainkey
selector1._domainkey
selector2._domainkey
default._domainkey
mail._domainkey
dkim._domainkey
k1._domainkey
s1._domainkey
s2._domainkey
zoho._domainkey
sendgrid._domainkey
mxvault._domainkey
amazonses._domainkey
✓ DKIM properly configured for selector: google
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
1 record- SPFv=spf1 -all
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