Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
gsb.columbia.edu
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-18 05:44:54 UTC · ↺ Refresh
MX Hostnames
- gsb-columbia-edu.mail.protection.outlook.com
MX Priorities
- gsb-columbia-edu.mail.protection.outlook.com: 10
A / AAAA Records
- 128.59.44.55 ↩ miscredirect-prod.cc.columbia.edu
- 2002:803b:c702::803b:c702 (no PTR)
- 2002:803b:ac02::803b:ac02
- 2002:803b:5402::803b:5402
Mail Server IPs
- 52.101.41.6 ↩ mail-sj0pr03cu01406.inbound.protection.outlook.com
- 52.101.40.24 ↩ mail-cy5pr05cu00100.inbound.protection.outlook.com
- 52.101.10.5 ↩ mail-bn6pr04cu00105.inbound.protection.outlook.com
- 52.101.10.14 ↩ mail-bn6pr04cu00206.inbound.protection.outlook.com
- 2a01:111:f403:f912:: ↩ mail-cy5pr03cu00200.inbound.protection.outlook.com
- 2a01:111:f403:f901:: ↩ mail-mn2pr04cu00200.inbound.protection.outlook.com
- 2a01:111:f403:c931:: ↩ mail-sn1pr02cu00100.inbound.protection.outlook.com
- 2a01:111:f403:c922:: ↩ mail-bl0pr03cu00200.inbound.protection.outlook.com
SOA Record
Raw SOA
ext-ns1.columbia.edu hostmaster.columbia.edu 1863 3600 1800 2419200 300
Primary NS (mname)
ext-ns1.columbia.edu
Admin Email (rname)
hostmaster@columbia.edu
Serial
1863
Refresh
3600s
Retry
1800s
Expire
2419200s
Minimum TTL
300s
Nameservers (NS)
auth1.dns.cogentco.com
ext-ns1.columbia.edu
auth2.dns.cogentco.com
SPF Record
✓ Soft Fail (~all)
v=spf1 include:%{ir}.%{v}.%{d}.spf.has.pphosted.com ~all
📊 DNS lookups: 1/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none; rua=mailto:[email protected]; ruf=mailto:[email protected]; rf=afrf; sp=none; pct=100; ri=86400
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
↳ Subdomain policy: none
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- SPFv=spf1 include:%{ir}.%{v}.%{d}.spf.has.pphosted.com ~all
- Ur9ziu+EQ16ELR4w/bdBbI6sJO4GY08zuDE/AxZkiqgUFzuwMAkJAar5iSDQMO1XEngjNEmsA6e1cqkXCcrPDA==
- 00d1i000000mhoyuaa
- MS=ms27984475
- pardot_48172_*=8f2f3e94d4e16f1870fe3b6ef7ba5bde95d6cd2d40804965ce2377a61c329382
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