Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
redstoneco.com
Yes
✓ Yes
Mimecast
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-20 21:34:19 UTC · ↺ Refresh
MX Hostnames
- us-smtp-inbound-1.mimecast.com
- us-smtp-inbound-2.mimecast.com
MX Priorities
- us-smtp-inbound-1.mimecast.com: 10
- us-smtp-inbound-2.mimecast.com: 10
A / AAAA Records
- 104.21.51.119 (no PTR)
- 172.67.180.43 (no PTR)
- 2606:4700:3035::6815:3377 (no PTR)
- 2606:4700:3033::ac43:b42b (no PTR)
Mail Server IPs
- 170.10.132.221 ↩ us-smtp-inbound-1.mimecast.com
- 170.10.132.242 ↩ us-smtp-inbound-2.mimecast.com
- 170.10.128.141 ↩ us-smtp-inbound-2.mimecast.com
- 170.10.132.141 ↩ us-smtp-inbound-1.mimecast.com
- 170.10.128.221 ↩ us-smtp-inbound-2.mimecast.com
- 170.10.128.242 ↩ us-smtp-inbound-1.mimecast.com
SOA Record
Raw SOA
ns1.ecidns.net dns.cloudflare.com 2399371057 10000 2400 604800 1800
Primary NS (mname)
ns1.ecidns.net
Admin Email (rname)
dns@cloudflare.com
Serial
2399371057
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s
Nameservers (NS)
ns4.ecidns.net
ns1.ecidns.net
ns2.ecidns.net
ns3.ecidns.net
SPF Record
✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com include:sendgrid.net include:mailgun.org include:us._netblocks.mimecast.com -all
📊 DNS lookups: 4/10
✓ 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
✓ 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
3 records- ZOOM_verify_2xlDbu02k1ouEotYSTUYRV
- SPFv=spf1 include:spf.protection.outlook.com include:sendgrid.net include:mailgun.org include:us._netblocks.mimecast.com -all
- MS=ms64132917
Full email verification for redstoneco.com
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