Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
rdn-online.de
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-04-02 15:30:07 UTC · ↺ Refresh
MX Hostnames
- rdnonline-de0i.mail.protection.outlook.com
MX Priorities
- rdnonline-de0i.mail.protection.outlook.com: 10
A / AAAA Records
- 217.160.0.220 ↩ 217-160-0-220.elastic-ssl.ui-r.com
- 2001:8d8:100f:f000::227 ↩ 2001-08d8-100f-f000-0000-0000-0000-0227.elastic-ssl.ui-r.com
Mail Server IPs
- 52.101.170.0 ↩ mail-fr5p281cu00500.inbound.protection.outlook.com
- 52.101.170.1 ↩ mail-fr4p281cu03101.inbound.protection.outlook.com
- 52.101.170.2 ↩ mail-fr6p281cu00202.inbound.protection.outlook.com
- 52.101.168.0 ↩ mail-beup281cu00100.inbound.protection.outlook.com
- 2a01:111:f403:ca2d::1 ↩ mail-fr4p281cu03101.inbound.protection.outlook.com
- 2a01:111:f403:ca2d:: ↩ mail-fr5p281cu00500.inbound.protection.outlook.com
- 2a01:111:f403:ca27:: ↩ mail-beup281cu00100.inbound.protection.outlook.com
- 2a01:111:f403:ca2d::2 ↩ mail-fr6p281cu00202.inbound.protection.outlook.com
SOA Record
Raw SOA
ns1032.ui-dns.de hostmaster.1und1.de 2016071726 28800 7200 604800 300
Primary NS (mname)
ns1032.ui-dns.de
Admin Email (rname)
hostmaster@1und1.de
Serial
2016071726
Refresh
28800s
Retry
7200s
Expire
604800s
Minimum TTL
300s
Nameservers (NS)
ns1032.ui-dns.org
ns1032.ui-dns.com
ns1032.ui-dns.biz
ns1032.ui-dns.de
SPF Record
✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com include:_spf.zimpel.de -all
📊 DNS lookups: 2/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none; rua=mailto:[email protected]
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 1 found
mail._domainkey
✓ Public key: 216 chars (valid)
✓ DKIM properly configured for selector: mail
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
6 records- brevo-code:b395f64166ae8f3fcd5818d9e259ae6b
- brevo-code:fefb7646b46594f995a4973015a5de1d
- sophos-domain-verification=e21277f54fb494044db1237b5c70ea0a87ff471c3f40906183101da30f8f3926
- SPFv=spf1 include:spf.protection.outlook.com include:_spf.zimpel.de -all
- sophos-domain-verification=f360094b9f546bdd99d93c5755664acbe02169331255f11c2698b4e88def1e19
- google-site-verification=8wqp1xFmJhzLU5ac6FrL1v7hr_hIAP5KSzBuLIwhxjQ
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