Domain Overview
DNS: ✓ just now
Checker: ✓ just now
hbg-troisdorf.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-09-04 18:29:45 UTC · ↺ Refresh
MX Hostnames
- mx.schulon.org
MX Priorities
- mx.schulon.org: 10
A / AAAA Records
- 217.239.225.194 (no PTR)
Mail Server IPs
- 194.77.246.20 ↩ mx.schulon.org
SOA Record
Raw SOA
dns.krzn.de jt.schulon.org 2023072602 86400 7200 604800 86400
Primary NS (mname)
dns.krzn.de
Admin Email (rname)
jt@schulon.org
Serial
2023072602
Refresh
86400s
Retry
7200s
Expire
604800s
Minimum TTL
86400s
Nameservers (NS)
secondary006.dtag.net
pns.dtag.de
dns.krzn.de
SPF Record
✓ Soft Fail (~all)
v=spf1 include:_spf.lgn.ext.schulon.org ~all
📊 DNS lookups: 1/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
✗ MissingNo DMARC record — emails cannot be rejected on auth failure.
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
⚠ Public key (p=) missing in DKIM record for selector google.
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
1 record- SPFv=spf1 include:_spf.lgn.ext.schulon.org ~all
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