Domain Overview
DNS: ✓ 2d ago
Checker: ✓ 2d ago
stirlingultracold.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-05-19 07:57:28 UTC · ↺ Refresh
MX Hostnames
- mx-cluster-usa01.hornetsecurity.com
- mx-cluster-usa04.hornetsecurity.com
- stirlingultracold-com.mail.protection.outlook.com
- mx-cluster-usa03.hornetsecurity.com
- mx-cluster-usa02.hornetsecurity.com
MX Priorities
- mx-cluster-usa04.hornetsecurity.com: 40
- stirlingultracold-com.mail.protection.outlook.com: 50
- mx-cluster-usa01.hornetsecurity.com: 10
- mx-cluster-usa02.hornetsecurity.com: 20
- mx-cluster-usa03.hornetsecurity.com: 30
A / AAAA Records
- 104.21.55.13 (no PTR)
- 172.67.143.235
- 2606:4700:3033::ac43:8feb
- 2606:4700:3036::6815:370d
Mail Server IPs
- 173.45.18.100 ↩ hsmx01-hz5.hornetsecurity.com
- 52.101.10.2 ↩ mail-bn8pr03cu00202.inbound.protection.outlook.com
- 52.101.194.15 ↩ mail-ch4pr21cu00107.inbound.protection.outlook.com
- 52.101.11.19 ↩ mail-sa9pr04cu00203.inbound.protection.outlook.com
- 52.101.50.7 ↩ mail-co1pr21cu00207.inbound.protection.outlook.com
- 2a01:111:f403:c91d::a ↩ mail-co1pr21cu00202.inbound.protection.outlook.com
- 2a01:111:f403:c931::1 ↩ mail-sa9pr03cu00201.inbound.protection.outlook.com
- 2a01:111:f403:c902::4 ↩ mail-sj0pr03cu01504.inbound.protection.outlook.com
- 2a01:111:f403:f90d:: ↩ mail-sn1pr0501cu00200.inbound.protection.outlook.com
SOA Record
Raw SOA
eric.ns.cloudflare.com dns.cloudflare.com 2401201852 10000 2400 604800 1800
Primary NS (mname)
eric.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2401201852
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s
Nameservers (NS)
eric.ns.cloudflare.com
rayne.ns.cloudflare.com
SPF Record
✓ Soft Fail (~all)
v=spf1 ip4:66.96.128.0/18 include:aspmx.pardot.com include:spf.workfront.com include:spf.hornetsecurity.com include:sendgrid.net include:8640746.spf07.hubspotemail.net include:spf.US.exclaimer.net include:_spf.salesforce.com ~all
📊 DNS lookups: 7/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
⚠ No aggregate reports (rua= not set)
DKIM Selectors
✓ 3 found
selector1._domainkey
selector2._domainkey
default._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
4 records- tpcfegbgfv1bl8mhbie73h4npe
- SPFv=spf1 ip4:66.96.128.0/18 include:aspmx.pardot.com include:spf.workfront.com include:spf.hornetsecurity.com include:sendgrid.net include:8640746.spf07.hubspotemail.net include:spf.US.exclaimer.net include:_spf.salesforce.com ~all
- cp8p13368tctgrs1rco06j9m9s
- pardot698883=29134ed12ab9f7ba4f19fcd5786d173e7ec3910d9afc622db0ffe188a4d96c1a
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