Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
str.us
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-30 02:49:27 UTC · ↺ Refresh
MX Hostnames
- stresearchcorp.mail.protection.office365.us
MX Priorities
- stresearchcorp.mail.protection.office365.us: 0
A / AAAA Records
- 72.167.107.157 ↩ 157.107.167.72.host.secureserver.net
Mail Server IPs
- 23.103.199.138 ↩ mail-bn3usg020138.inbound.protection.outlook.com
- 23.103.199.170 ↩ mail-cy1usg020170.inbound.protection.outlook.com
SOA Record
Raw SOA
ns43.domaincontrol.com dns.jomax.net 2026031800 28800 7200 604800 600
Primary NS (mname)
ns43.domaincontrol.com
Admin Email (rname)
dns@jomax.net
Serial
2026031800
Refresh
28800s
Retry
7200s
Expire
604800s
Minimum TTL
600s
Nameservers (NS)
ns44.domaincontrol.com
ns43.domaincontrol.com
SPF Record
✓ Strict (-all)
v=spf1 include:spf.protection.office365.us ip4:40.139.55.96/28 ip4:18.253.124.174/32 ip4:50.231.90.221/32 -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; rua=mailto:[email protected], mailto:[email protected];
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected], mailto:[email protected]
DKIM Selectors
✓ 2 found
selector1._domainkey
selector2._domainkey
✓ Public key: 216 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
2 records- SPFv=spf1 include:spf.protection.office365.us ip4:40.139.55.96/28 ip4:18.253.124.174/32 ip4:50.231.90.221/32 -all
- MS=ms60282395
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