Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
osf.com
Yes
✓ Yes
Mimecast
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-18 21:16:18 UTC · ↺ Refresh
MX Hostnames
- usb-smtp-inbound-1.mimecast.com
- usb-smtp-inbound-2.mimecast.com
MX Priorities
- usb-smtp-inbound-2.mimecast.com: 5
- usb-smtp-inbound-1.mimecast.com: 5
A / AAAA Records
- 104.21.75.122 (no PTR)
- 172.67.175.150 (no PTR)
- 2606:4700:3036::ac43:af96 (no PTR)
- 2606:4700:3032::6815:4b7a (no PTR)
Mail Server IPs
- 170.10.150.242 ↩ usb-smtp-delivery-2.mimecast.com
SOA Record
Raw SOA
drew.ns.cloudflare.com dns.cloudflare.com 2398369080 10000 2400 604800 1800
Primary NS (mname)
drew.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2398369080
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s
Nameservers (NS)
drew.ns.cloudflare.com
violet.ns.cloudflare.com
SPF Record
✓ Strict (-all)
v=spf1 include:usb._netblocks.mimecast.com a:osf-smtp.osf.com include:spf.protection.outlook.com -all
📊 DNS lookups: 3/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1; p=quarantine; rua=mailto:[email protected];
~ 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: 392 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- MS=ms78825633
- SPFv=spf1 include:usb._netblocks.mimecast.com a:osf-smtp.osf.com include:spf.protection.outlook.com -all
Full email verification for osf.com
Run SMTP check, SPF/DKIM/DMARC and catch-all detection.
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