Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
sierraclassic.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-29 18:25:34 UTC · ↺ Refresh
MX Hostnames
- sierraclassic-com.mail.protection.outlook.com
MX Priorities
- sierraclassic-com.mail.protection.outlook.com: 10
A / AAAA Records
- 104.26.1.69 (no PTR)
- 172.67.70.248 (no PTR)
- 104.26.0.69
- 2606:4700:20::ac43:46f8
- 2606:4700:20::681a:145
- 2606:4700:20::681a:45
Mail Server IPs
- 52.101.41.6 ↩ mail-sj0pr03cu01406.inbound.protection.outlook.com
- 52.101.41.180 ↩ mail-byapr04cu00204.inbound.protection.outlook.com
- 52.101.11.10 ↩ mail-sa9pr03cu00202.inbound.protection.outlook.com
- 52.101.194.13 ↩ mail-ch0pr04cu00605.inbound.protection.outlook.com
- 2a01:111:f403:f90f:: ↩ mail-sa9pr04cu00100.inbound.protection.outlook.com
- 2a01:111:f403:f910:: ↩ mail-cy5pr03cu00300.inbound.protection.outlook.com
- 2a01:111:f403:c803:: ↩ mail-bn1pr21cu00200.inbound.protection.outlook.com
- 2a01:111:f403:c901::1 ↩ mail-bl2pr04cu00201.inbound.protection.outlook.com
SOA Record
Raw SOA
brenda.ns.cloudflare.com dns.cloudflare.com 2397265009 10000 2400 604800 1800
Primary NS (mname)
brenda.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2397265009
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s
Nameservers (NS)
brenda.ns.cloudflare.com
thaddeus.ns.cloudflare.com
SPF Record
✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none; rua=mailto:[email protected];
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 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
3 records- facebook-domain-verification=mhk06ya1zox5h2ncn4081sghx2dzam
- google-site-verification=E7Ph0pYsW4dQxNr3Vm2wnA1NB25rCz9ee3ij6oI3aBQ
- SPFv=spf1 include:spf.protection.outlook.com -all
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