Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
holborn.ca
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-04-01 14:40:05 UTC · ↺ Refresh
MX Hostnames
- holborn-ca.mail.protection.outlook.com
MX Priorities
- holborn-ca.mail.protection.outlook.com: 0
A / AAAA Records
- 172.105.3.30 ↩ 172-105-3-30.ip.linodeusercontent.com
Mail Server IPs
- 52.101.190.1 ↩ mail-yt3pr01cu00701.inbound.protection.outlook.com
- 52.101.190.3 ↩ mail-yt6pr01cu00103.inbound.protection.outlook.com
- 52.101.192.1 ↩ mail-yqzpr01cu01001.inbound.protection.outlook.com
- 52.101.192.0 ↩ mail-yqzpr01cu00900.inbound.protection.outlook.com
- 2a01:111:f403:c942::1 ↩ mail-yt3pr01cu00701.inbound.protection.outlook.com
- 2a01:111:f403:c942::3 ↩ mail-yt6pr01cu00103.inbound.protection.outlook.com
- 2a01:111:f403:c942::2 ↩ mail-yt3pr01cu00602.inbound.protection.outlook.com
- 2a01:111:f403:c944::1 ↩ mail-yqzpr01cu01001.inbound.protection.outlook.com
SOA Record
Raw SOA
aldo.ns.cloudflare.com dns.cloudflare.com 2400511026 10000 2400 604800 1800
Primary NS (mname)
aldo.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2400511026
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s
Nameservers (NS)
cass.ns.cloudflare.com
aldo.ns.cloudflare.com
SPF Record
✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com include:mailgun.org include:spf-westus.emailsignatures365.com -all
📊 DNS lookups: 3/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1; p=quarantine; pct=100; rua=mailto:[email protected]; ruf=mailto:[email protected]
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 2 found
selector1._domainkey
selector2._domainkey
✓ DKIM properly configured for selector: selector1
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
6 records- sophos-domain-verification=31ee80a20007b977a7693915959ca3902b4560c520f063ed38faf89d649878ed
- sophos-domain-verification=f8cc520ee38f74a2373e02d0c791410ab9efa4e5
- SPFv=spf1 include:spf.protection.outlook.com include:mailgun.org include:spf-westus.emailsignatures365.com -all
- google-site-verification=pnFwBwgl7jF2huy5VDbRsrLXHShQEYP6Y87GHjQzxz0
- google-site-verification=yWrzufT4rfD_43rtXihXGiD7VzFPLzEPlnlPAKkFpdc
- google-site-verification=z65f1nqOFmWCmvDFdNAPP9PpBmR6HKg8w4rhTlaHQzc
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