Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
sierracon.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-23 20:24:33 UTC · ↺ Refresh
MX Hostnames
- sierracon-com.mail.protection.outlook.com
MX Priorities
- sierracon-com.mail.protection.outlook.com: 0
A / AAAA Records
- 209.17.116.160 (no PTR)
Mail Server IPs
- 40.93.192.1 ↩ mail-dm5pr02cu00201.inbound.protection.outlook.com
- 52.101.41.6 ↩ mail-sj0pr03cu01406.inbound.protection.outlook.com
- 52.101.50.13 ↩ mail-mw2pr02cu00605.inbound.protection.outlook.com
- 52.101.42.14 ↩ mail-mw2pr04cu00106.inbound.protection.outlook.com
- 2a01:111:f403:f912:: ↩ mail-cy5pr03cu00200.inbound.protection.outlook.com
- 2a01:111:f403:f90d::1 ↩ mail-sn1pr0501cu00301.inbound.protection.outlook.com
- 2a01:111:f403:f908:: ↩ mail-bn1pr21cu00100.inbound.protection.outlook.com
- 2a01:111:f403:c927::1 ↩ mail-bn8pr05cu00301.inbound.protection.outlook.com
SOA Record
Raw SOA
ns31.worldnic.com namehost.worldnic.com 124073011 10800 3600 604800 3600
Primary NS (mname)
ns31.worldnic.com
Admin Email (rname)
namehost@worldnic.com
Serial
124073011
Refresh
10800s
Retry
3600s
Expire
604800s
Minimum TTL
3600s
Nameservers (NS)
ns32.worldnic.com
ns31.worldnic.com
SPF Record
✓ Soft Fail (~all)
v=spf1 include:one.zoho.com include:spf.protection.outlook.com ~all
📊 DNS lookups: 2/10
~ Soft fail (~all) — moderate 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
✓ 3 found
selector1._domainkey
selector2._domainkey
s1._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
1 record- SPFv=spf1 include:one.zoho.com include:spf.protection.outlook.com ~all
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