Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
sibley.org
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-21 14:34:27 UTC · ↺ Refresh
MX Hostnames
- smtp.johnshopkins.edu
MX Priorities
- smtp.johnshopkins.edu: 10
A / AAAA Records
- 162.129.193.2 (no PTR)
Mail Server IPs
- 128.220.38.15 ↩ smtp.johnshopkins.edu
- 162.129.199.4 (no PTR)
SOA Record
Raw SOA
ens1.jhu.edu hostmaster.jhu.edu 2014014005 10800 3600 2419200 900
Primary NS (mname)
ens1.jhu.edu
Admin Email (rname)
hostmaster@jhu.edu
Serial
2014014005
Refresh
10800s
Retry
3600s
Expire
2419200s
Minimum TTL
900s
Nameservers (NS)
ens1.jhu.edu
ens1.jhmi.edu
SPF Record
✗ MissingNo SPF record — domain is unprotected against spoofing.
⚠ No SPF record found. Email servers cannot verify authorized senders.
DMARC Record
~ Quarantine
v=DMARC1; p=quarantine; rua=mailto:[email protected]; ruf=mailto:[email protected];
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✗ None detectedNo DKIM records found for common selectors — your provider may use a custom selector name.
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
No TXT records found.
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