Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
rkb.de
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-04-04 17:27:05 UTC · ↺ Refresh
MX Hostnames
- rkb-de.mail.protection.outlook.com
MX Priorities
- rkb-de.mail.protection.outlook.com: 0
A / AAAA Records
- 85.13.157.10 ↩ dd39434.kasserver.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::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
- 2a01:111:f403:ca2d::1 ↩ mail-fr4p281cu03101.inbound.protection.outlook.com
SOA Record
Raw SOA
ns5.kasserver.com hostmaster.kasserver.com 2603230047 28800 7200 1209600 7200
Primary NS (mname)
ns5.kasserver.com
Admin Email (rname)
hostmaster@kasserver.com
Serial
2603230047
Refresh
28800s
Retry
7200s
Expire
1209600s
Minimum TTL
7200s
Nameservers (NS)
ns5.kasserver.com
ns3.ai-dns.de
ns6.kasserver.com
ns5.name-server-kas.de
SPF Record
✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com include:spf.cloud.ci-solution.com -all
📊 DNS lookups: 2/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1; p=quarantine;
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
⚠ No aggregate reports (rua= not set)
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
2 records- MS=ms34824766
- SPFv=spf1 include:spf.protection.outlook.com include:spf.cloud.ci-solution.com -all
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