Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
rmkb.com
Yes
✓ Yes
Mimecast
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-20 21:44:04 UTC · ↺ Refresh
MX Hostnames
- us-smtp-inbound-2.mimecast.com
- us-smtp-inbound-1.mimecast.com
MX Priorities
- us-smtp-inbound-2.mimecast.com: 10
- us-smtp-inbound-1.mimecast.com: 10
A / AAAA Records
- 76.76.21.21 (no PTR)
Mail Server IPs
- 170.10.132.242 ↩ us-smtp-inbound-2.mimecast.com
- 170.10.128.221 ↩ us-smtp-inbound-2.mimecast.com
- 170.10.128.242 ↩ us-smtp-inbound-1.mimecast.com
- 170.10.132.221 ↩ us-smtp-inbound-1.mimecast.com
- 170.10.128.141 ↩ us-smtp-inbound-2.mimecast.com
- 170.10.132.141 ↩ us-smtp-inbound-1.mimecast.com
SOA Record
Raw SOA
ns11.constellix.com dns.constellix.com 2015010138 43200 3600 1209600 180
Primary NS (mname)
ns11.constellix.com
Admin Email (rname)
dns@constellix.com
Serial
2015010138
Refresh
43200s
Retry
3600s
Expire
1209600s
Minimum TTL
180s
Nameservers (NS)
ns11.constellix.com
ns21.constellix.com
ns31.constellix.com
ns41.constellix.net
ns51.constellix.net
ns61.constellix.net
SPF Record
✓ Strict (-all)
v=spf1 include:us._netblocks.mimecast.com -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; rua=mailto:[email protected]; ruf=mailto:[email protected]; adkim=s; aspf=s; fo=1;
✓ Reject — strongest protection
📋 SPF alignment: Strict
· DKIM alignment: Strict
📧 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
1 record- SPFv=spf1 include:us._netblocks.mimecast.com -all
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