Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
tandem-kommunikation.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-04-04 07:33:45 UTC · ↺ Refresh
MX Hostnames
- mx01.leitwerk.net
- mx02.leitwerk.net
MX Priorities
- mx01.leitwerk.net: 10
- mx02.leitwerk.net: 10
A / AAAA Records
- 217.28.97.113 ↩ leitwerk.net
- 2a02:ba8:97:64:250:56ff:fe8f:d614 ↩ leitwerk.net
Mail Server IPs
- 217.28.97.116 ↩ mx01.leitwerk.net
- 2a02:ba8:97:64:250:56ff:fe88:6ba9 ↩ mx01.leitwerk.net
- 217.28.97.118 ↩ mx02.leitwerk.net
- 2a02:ba8:97:64:250:56ff:fe88:4a1f ↩ mx02.leitwerk.net
SOA Record
Raw SOA
ns.leitwerk.net noc.leitwerk.net 2025051900 28800 7200 604800 86400
Primary NS (mname)
ns.leitwerk.net
Admin Email (rname)
noc@leitwerk.net
Serial
2025051900
Refresh
28800s
Retry
7200s
Expire
604800s
Minimum TTL
86400s
Nameservers (NS)
ns3.baden.domains
ns.leitwerk.net
SPF Record
✓ Strict (-all)
v=spf1 include:_spf.leitwerk.net include:spf.protection.outlook.com include:spf-de.emailsignatures365.com -all
📊 DNS lookups: 3/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1; p=quarantine; rua=mailto:[email protected]; pct=100;
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 2 found
selector1._domainkey
selector2._domainkey
✓ Public key: 216 chars (valid)
✓ DKIM properly configured for selector: selector1
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
1 record- SPFv=spf1 include:_spf.leitwerk.net include:spf.protection.outlook.com include:spf-de.emailsignatures365.com -all
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