Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
luettgens.de
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-21 05:50:21 UTC · ↺ Refresh
MX Hostnames
- luettgens-de.mail.protection.outlook.com
MX Priorities
- luettgens-de.mail.protection.outlook.com: 0
A / AAAA Records
- 188.64.57.89 ↩ web16.transresult.net
Mail Server IPs
- 52.101.170.1 ↩ mail-fr4p281cu03101.inbound.protection.outlook.com
- 52.101.168.0 ↩ mail-beup281cu00100.inbound.protection.outlook.com
- 52.101.170.0 ↩ mail-fr5p281cu00500.inbound.protection.outlook.com
- 52.101.170.2 ↩ mail-fr6p281cu00202.inbound.protection.outlook.com
- 2a01:111:f403:ca2d::1 ↩ mail-fr4p281cu03101.inbound.protection.outlook.com
- 2a01:111:f403:ca2d::2 ↩ mail-fr6p281cu00202.inbound.protection.outlook.com
- 2a01:111:f403:ca27:: ↩ mail-beup281cu00100.inbound.protection.outlook.com
- 2a01:111:f403:ca2d:: ↩ mail-fr5p281cu00500.inbound.protection.outlook.com
SOA Record
Raw SOA
a.dns-i.net hostmaster.insyst.de 2023121412 28800 7200 1209600 1800
Primary NS (mname)
a.dns-i.net
Admin Email (rname)
hostmaster@insyst.de
Serial
2023121412
Refresh
28800s
Retry
7200s
Expire
1209600s
Minimum TTL
1800s
Nameservers (NS)
a.dns-i.net
c.dns-i.net
b.dns-i.net
SPF Record
✓ Strict (-all)
v=spf1 a include:spf.insyst.de include:spf.protection.outlook.com ip4:87.128.57.201 -all
📊 DNS lookups: 3/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none; rua=mailto:[email protected],mailto:[email protected]; ruf=mailto:[email protected]; pct=100; fo=1; adkim=s; aspf=s
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Strict
· DKIM alignment: Strict
📧 Reports → mailto:[email protected],mailto:[email protected]
DKIM Selectors
✓ 2 found
selector1._domainkey
selector2._domainkey
✓ Public key: 392 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 a include:spf.insyst.de include:spf.protection.outlook.com ip4:87.128.57.201 -all
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