principalhvac.com

Valid Email Server
Domain Lookup › principalhvac.com

Domain Overview

DNS: ✓ 2mo ago Checker: ✓ 2mo ago
principalhvac.com
Yes
✓ Yes
Barracuda
No
No
⚠ Yes
No
No

Checked via [email protected] · 2026-03-20 07:38:11 UTC · ↺ Refresh

MX Hostnames

  • d232576.b.ess.uk.barracudanetworks.com
  • d232576.a.ess.uk.barracudanetworks.com

MX Priorities

  • d232576.b.ess.uk.barracudanetworks.com: 40
  • d232576.a.ess.uk.barracudanetworks.com: 10

A / AAAA Records

  • 185.151.30.146 ↩ 185-151-30-146.ptr4.stackcp.net

Mail Server IPs

  • 18.133.136.187 ↩ mail.ess.uk.barracuda.com
  • 18.133.136.186 ↩ mail.ess.uk.barracuda.com
  • 18.133.136.188 ↩ mail.ess.uk.barracuda.com

SOA Record

Raw SOA ns1.blacknight.com hostmaster.blacknight.com 1276194346 14400 7200 2419200 3600
Primary NS (mname)
ns1.blacknight.com
Admin Email (rname)
hostmaster@blacknight.com
Serial
1276194346
Refresh
14400s
Retry
7200s
Expire
2419200s
Minimum TTL
3600s

Nameservers (NS)

ns3.blacknight.com
ns2.blacknight.com
ns1.blacknight.com
ns4.blacknight.com

SPF Record

✓ Strict (-all)
v=spf1 include:spf.ess.uk.barracudanetworks.com include:spf.exclaimer.net include:spf.protection.outlook.com a:principalhvac.com ip4:81.149.20.133 -all
📊 DNS lookups: 4/10
✓ Hard fail (-all) — strict enforcement

DMARC Record

✗ Missing

No DMARC record — emails cannot be rejected on auth failure.

DKIM Selectors

✗ None detected

No DKIM records found for common selectors — your provider may use a custom selector name.

Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses

All TXT Records

2 records
  • SPFv=spf1 include:spf.ess.uk.barracudanetworks.com include:spf.exclaimer.net include:spf.protection.outlook.com a:principalhvac.com ip4:81.149.20.133 -all
  • google-site-verification=E9qivjkasdz17NkVGUqojw3iDrPXKd3Z1ImWRVr0bS8
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