Live data — DNS records and disposable check were just fetched and saved.
Domain Overview
DNS: ⚡ live
Checker: ⚡ live
sierrainstruments.com
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-05-21 06:07:46 UTC · ↺ Refresh
MX Hostnames
- us1-smtp-mx1.titanhq.com
- us1-smtp-mx2.titanhq.com
MX Priorities
No priority data.
A / AAAA Records
- 52.32.224.216
Mail Server IPs
No IPs resolved.
SOA Record
No SOA record found.
Nameservers (NS)
dns2.registrar-servers.com
dns1.registrar-servers.com
SPF Record
✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com include:7893883.spf05.hubspotemail.net include:_phishspf.knowbe4.com include:em5278.sierrainstruments.com -all
📊 DNS lookups: 4/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✓ Reject
v=DMARC1;p=reject;sp=reject;pct=100;rua=mailto:[email protected];ruf=mailto:[email protected];ri=86400;fo=1;
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
↳ Subdomain policy: reject
DKIM Selectors
✓ 4 found
selector1._domainkey
selector2._domainkey
s1._domainkey
s2._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
10 records- openai-domain-verification=dv-rWQ0wnya2ull8ERiHUFBdN46
- knowbe4-site-verification=36e54efe69ef560cad4e9e7a6ae77fb5
- ms-domain-verification=43965721-51c0-4848-a9f7-9a34a9f7ac13
- anthropic-domain-verification-zxrq0z=3Pn4K375RwTjCBdFUCbD5fB8i
- perplexity-ai-domain-verification-d3ra6w=WYxmIfoqwWG7rJcV9JDp1BvWI
- google-site-verification=GC67YtBaXnzLlnb9CgLqUze-_JzmE0GLlOv_ff6XvSU
- atlassian-domain-verification=XW4d41LZGc8JnDJv7BIvV5/0/R+MWEbno7PqYR1x51e9DFdUwrf2PfymLBvWe7Hg
- SPFv=spf1 include:spf.protection.outlook.com include:7893883.spf05.hubspotemail.net include:_phishspf.knowbe4.com include:em5278.sierrainstruments.com -all
- MS=ms19338341
- apple-domain-verification=gVBPNZWIsjDmbqrU
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