Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
tubus-gmbh.de
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-27 09:12:37 UTC · ↺ Refresh
MX Hostnames
- tubusgmbh-de01c.mail.protection.outlook.com
MX Priorities
- tubusgmbh-de01c.mail.protection.outlook.com: 10
A / AAAA Records
- 81.169.145.165 ↩ wa5.rzone.de
- 2a01:238:20a:202:1165:: ↩ wa5.rzone.de
Mail Server IPs
- 52.101.185.13 ↩ mail-zrzp278cu00205.inbound.protection.outlook.com
- 52.101.185.14 ↩ mail-zr1p278cu00206.inbound.protection.outlook.com
- 52.101.187.1 ↩ mail-gvap278cu00301.inbound.protection.outlook.com
- 52.101.185.12 ↩ mail-zrap278cu00304.inbound.protection.outlook.com
- 2a01:111:f403:ca3c::1 ↩ mail-zrzp278cu00201.inbound.protection.outlook.com
- 2a01:111:f403:ca3c::2 ↩ mail-zr1p278cu00202.inbound.protection.outlook.com
- 2a01:111:f403:ca3c:: ↩ mail-zrap278cu00300.inbound.protection.outlook.com
- 2a01:111:f403:ca3e::1 ↩ mail-gvap278cu00301.inbound.protection.outlook.com
SOA Record
Raw SOA
shades20.rzone.de hostmaster.strato-rz.de 2020050831 86400 7200 604800 300
Primary NS (mname)
shades20.rzone.de
Admin Email (rname)
hostmaster@strato-rz.de
Serial
2020050831
Refresh
86400s
Retry
7200s
Expire
604800s
Minimum TTL
300s
Nameservers (NS)
shades20.rzone.de
docks06.rzone.de
SPF Record
✓ Strict (-all)
v=spf1 mx a include:_spf.strato.com include:spf.protection.outlook.com -all
📊 DNS lookups: 4/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; rua=mailto:[email protected]; ruf=mailto:[email protected]; sp=reject; adkim=s; fo=0;
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Strict
📧 Reports → mailto:[email protected]
↳ Subdomain policy: reject
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
3 records- MS=ms21343958
- knowbe4-site-verification=3ea4888fa32244050ab05e6f8eba70a4
- SPFv=spf1 mx a include:_spf.strato.com include:spf.protection.outlook.com -all
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