Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
rational-online.es
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-22 08:02:34 UTC · ↺ Refresh
MX Hostnames
- rationalonline-es02b.mail.protection.outlook.com
MX Priorities
- rationalonline-es02b.mail.protection.outlook.com: 5
A / AAAA Records
- 51.116.176.235 (no PTR)
Mail Server IPs
- 52.101.68.21 ↩ mail-db4pr02cu00205.inbound.protection.outlook.com
- 52.101.68.15 ↩ mail-db6pr03cu00107.inbound.protection.outlook.com
- 52.101.68.0 ↩ mail-db3pr0202cu00100.inbound.protection.outlook.com
- 52.101.73.28 ↩ mail-am7pr05cu00204.inbound.protection.outlook.com
- 2a01:111:f403:ca09::e ↩ mail-am7pr05cu00206.inbound.protection.outlook.com
- 2a01:111:f403:ca04::9 ↩ mail-db7pr03cu00601.inbound.protection.outlook.com
- 2a01:111:f403:ca04::10 ↩ mail-dbapr03cu00100.inbound.protection.outlook.com
- 2a01:111:f403:ca09::9 ↩ mail-as8pr04cu00801.inbound.protection.outlook.com
SOA Record
Raw SOA
ns1-06.azure-dns.com hostmaster.rational-online.com 2020040801 10800 7200 604800 360
Primary NS (mname)
ns1-06.azure-dns.com
Admin Email (rname)
hostmaster@rational-online.com
Serial
2020040801
Refresh
10800s
Retry
7200s
Expire
604800s
Minimum TTL
360s
Nameservers (NS)
ns4-06.azure-dns.info
ns1-06.azure-dns.com
ns2-06.azure-dns.net
ns3-06.azure-dns.org
SPF Record
✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1;p=quarantine;pct=100;rua=mailto:[email protected];ruf=mailto:[email protected];adkim=s;aspf=s
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Strict
· DKIM alignment: Strict
📧 Reports → 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
2 records- MS=ms41239310
- SPFv=spf1 include:spf.protection.outlook.com -all
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