Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
houstonisd.org
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-21 01:02:24 UTC · ↺ Refresh
MX Hostnames
- houstonisd-org.mail.protection.outlook.com
MX Priorities
- houstonisd-org.mail.protection.outlook.com: 10
A / AAAA Records
- 104.17.71.73 (no PTR)
Mail Server IPs
- 40.93.192.4 ↩ mail-dm2pr04cu00404.inbound.protection.outlook.com
- 52.101.11.17 ↩ mail-sn1pr0501cu00301.inbound.protection.outlook.com
- 52.101.9.21 ↩ mail-bl2pr04cu00205.inbound.protection.outlook.com
- 52.101.9.24 ↩ mail-bl2pr02cu00400.inbound.protection.outlook.com
- 2a01:111:f403:c946::7 ↩ mail-ch5pr02cu00307.inbound.protection.outlook.com
- 2a01:111:f403:f90f::1 ↩ mail-sa9pr04cu00201.inbound.protection.outlook.com
- 2a01:111:f403:c902::14 ↩ mail-byapr04cu00204.inbound.protection.outlook.com
- 2a01:111:f403:f907::1 ↩ mail-dm1pr04cu00201.inbound.protection.outlook.com
SOA Record
Raw SOA
ns-1428.awsdns-50.org awsdns-hostmaster.amazon.com 1 7200 900 1209600 86400
Primary NS (mname)
ns-1428.awsdns-50.org
Admin Email (rname)
awsdns-hostmaster@amazon.com
Serial
1
Refresh
7200s
Retry
900s
Expire
1209600s
Minimum TTL
86400s
Nameservers (NS)
ns-412.awsdns-51.com
ns-997.awsdns-60.net
ns-1428.awsdns-50.org
ns-1742.awsdns-25.co.uk
SPF Record
✓ Strict (-all)
v=spf1 ip4:166.127.112.179 include:amazonses.com include:sapsf.com include:_spf-sfdc.successfactors.com include:customerspf.schoolmessenger.com include:_spf.qualtrics.com include:spf.protection.outlook.com -all
📊 DNS lookups: 6/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1;p=quarantine;rua=mailto:[email protected];ruf=mailto:[email protected];ri=86400
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 4 found
selector1._domainkey
selector2._domainkey
s1._domainkey
s2._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- intersight=dd4a3db81d16782b44e2b19e7de7bade293e2f0d1974343ad56b0d8b72ca0560
- SPFv=spf1 ip4:166.127.112.179 include:amazonses.com include:sapsf.com include:_spf-sfdc.successfactors.com include:customerspf.schoolmessenger.com include:_spf.qualtrics.com include:spf.protection.outlook.com -all
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