Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
rational-online.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-30 05:42:18 UTC · ↺ Refresh
MX Hostnames
- rationalonline-com02b.mail.protection.outlook.com
MX Priorities
- rationalonline-com02b.mail.protection.outlook.com: 5
A / AAAA Records
- 51.116.176.235 (no PTR)
Mail Server IPs
- 52.101.73.15 ↩ mail-am9pr04cu00107.inbound.protection.outlook.com
- 52.101.73.11 ↩ mail-am1pr04cu00103.inbound.protection.outlook.com
- 52.101.68.8 ↩ mail-du0pr03cu00100.inbound.protection.outlook.com
- 52.101.68.21 ↩ mail-db4pr02cu00205.inbound.protection.outlook.com
- 2a01:111:f403:ca04::e ↩ mail-db8pr02cu00106.inbound.protection.outlook.com
- 2a01:111:f403:ca09::d ↩ mail-as9pr05cu01305.inbound.protection.outlook.com
- 2a01:111:f403:ca09::5 ↩ mail-am1pr04cu00105.inbound.protection.outlook.com
- 2a01:111:f403:ca04::b ↩ mail-dbbpr03cu00103.inbound.protection.outlook.com
SOA Record
Raw SOA
ns1-02.azure-dns.com hostmaster.rational-online.com 2020040801 10800 7200 604800 360
Primary NS (mname)
ns1-02.azure-dns.com
Admin Email (rname)
hostmaster@rational-online.com
Serial
2020040801
Refresh
10800s
Retry
7200s
Expire
604800s
Minimum TTL
360s
Nameservers (NS)
ns2-02.azure-dns.net
ns3-02.azure-dns.org
ns4-02.azure-dns.info
ns1-02.azure-dns.com
SPF Record
✓ Strict (-all)
v=spf1 include:_u.rational-online.com._spf.dmarclyeu.com ip4:212.34.64.185 -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1; p=quarantine; rua=mailto:[email protected]; ruf=mailto:[email protected]; sp=quarantine; adkim=s; aspf=s; pct=100; fo=0;
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Strict
· DKIM alignment: Strict
📧 Reports → mailto:[email protected]
↳ Subdomain policy: quarantine
DKIM Selectors
✓ 4 found
selector1._domainkey
selector2._domainkey
s1._domainkey
s2._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
15 records- autodesk-domain-verification=UhZDg4vPWJinu_y16NQz
- miro-verification=fc3ccaac48e40dda0e203614c2510a083615c7e3
- google-site-verification=zbpcOHBDpkbsUxsD5KHNH9FZkomTR5wgVjGTUfvhcY0
- google-site-verification=mzVA-ZyfAIGP0reTlGabtQyzzViYnOXvfhVh1urV24g
- detectify-verification=40457cf80b9fa21ee93787ddd107c950
- MS=ms96508373
- globalsign-domain-verification=asnCRhRiOLbEGFRO-Qmn7XtUc1llLZz8p0kCV4s-VR
- Pkk9S2P2Y8tdNSZrsxyFoFOVIX/oTTjcrfeCL/JV8RaLP8csfy8qCCsV0IXJukNxYmWXS10sJWO1E+N0XBcTag==
- swisssign-check=NEMA8RE1sHllEKMS2Lm_Z_yMR_c
- SPFv=spf1 include:_u.rational-online.com._spf.dmarclyeu.com ip4:212.34.64.185 -all
- apple-domain-verification=WOvNnpksh1FMexYK
- docusign=0b958393-9d33-4df0-a528-3db0c0e15eea
- mindmanager-verification=1998d3641ecbf8a19298b0441870cff5e80a3488ccf603ce6f48902ee61770ef
- teamviewer-sso-verification=85a576d9eb6e4d928ff95a6dcc20d484
- atlassian-domain-verification=3gcJIZOfwPgt0dtS5j2vdZDQyQYOS635L9fxe7EJl6IHsolGzbJNfrmV0eYROhtc
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