Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
c3boston.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-25 21:19:40 UTC · ↺ Refresh
MX Hostnames
- c3boston-com.mail.protection.outlook.com
MX Priorities
- c3boston-com.mail.protection.outlook.com: 20
A / AAAA Records
- 198.102.82.200 (no PTR)
Mail Server IPs
- 52.101.10.8 ↩ mail-bn1pr04cu00100.inbound.protection.outlook.com
- 52.101.9.20 ↩ mail-bl0pr02cu00604.inbound.protection.outlook.com
- 52.101.9.0 ↩ mail-bl2pr02cu00100.inbound.protection.outlook.com
- 52.101.9.5 ↩ mail-mn2pr04cu00205.inbound.protection.outlook.com
SOA Record
Raw SOA
a7.uberns.com noreply.rimkus.com 2603200001 14400 7200 1209600 300
Primary NS (mname)
a7.uberns.com
Admin Email (rname)
noreply@rimkus.com
Serial
2603200001
Refresh
14400s
Retry
7200s
Expire
1209600s
Minimum TTL
300s
Nameservers (NS)
a7.uberns.com
b7.uberns.com
SPF Record
✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1; p=quarantine; rua=mailto:[email protected]; ruf=mailto:[email protected]; fo=1
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 2 found
selector1._domainkey
selector2._domainkey
✓ DKIM properly configured for selector: selector1
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
5 records- autodesk-domain-verification=oIyCeDyUQyQ9Gd3_Yy7f
- knowbe4-site-verification=b029e5b8e9c563fa3d8f4986be15be11
- MS=ms78505436
- aklpcemafbdm1kuajsqrpmbaqc
- SPFv=spf1 include:spf.protection.outlook.com -all
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