3sisecurity.com

Valid Email Server

Domain Overview

DNS: ✓ 2mo ago Checker: ✓ 2mo ago
3sisecurity.com
Yes
✓ Yes
Mimecast
No
No
⚠ Yes
No
No

Checked via [email protected] · 2026-04-01 02:06:53 UTC · ↺ Refresh

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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

  • 167.71.242.134 ↩ 3sisecurity.com

Mail Server IPs

  • 170.10.128.242 ↩ us-smtp-inbound-1.mimecast.com
  • 170.10.128.221 ↩ us-smtp-inbound-1.mimecast.com
  • 170.10.132.221 ↩ us-smtp-inbound-2.mimecast.com
  • 170.10.132.141 ↩ us-smtp-inbound-1.mimecast.com
  • 170.10.132.242 ↩ us-smtp-inbound-1.mimecast.com
  • 170.10.128.141 ↩ us-smtp-inbound-1.mimecast.com

SOA Record

Raw SOA ns19.worldnic.com namehost.worldnic.com 126021708 10800 3600 604800 3600
Primary NS (mname)
ns19.worldnic.com
Admin Email (rname)
namehost@worldnic.com
Serial
126021708
Refresh
10800s
Retry
3600s
Expire
604800s
Minimum TTL
3600s

Nameservers (NS)

ns20.worldnic.com
ns19.worldnic.com

SPF Record

✓ Soft Fail (~all)
v=spf1 ip4:167.71.242.134 include:50112483.spf08.hubspotemail.net redirect=a9rit42c._spf._d.mim.ec
📊 DNS lookups: 2/10

DMARC Record

✗ p=none
v=DMARC1; p=none; rua=mailto:[email protected]; ruf=mailto:[email protected]; fo=1;
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed · DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]

DKIM Selectors

✓ 4 found
selector1._domainkey
selector2._domainkey
s1._domainkey
s2._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

9 records
  • atlassian-domain-verification=dsO6ELyEutHqTVeCMfy0VvCvZBoKu8N4fAZhLZaAkZkuBMtSBMGgSuSsEXAXAKAd
  • smartsheet-site-validation=9NNzKTdS1pGWEdsG8rYgw0TPIrlLfM88
  • gvecnb60c2mrf5c6uekg40hdss
  • SPFv=spf1 ip4:167.71.242.134 include:50112483.spf08.hubspotemail.net redirect=a9rit42c._spf._d.mim.ec
  • google-site-verification=Fdq9ac_P3IIDSEFmEQJExivqpQRAsOS61b2lZDMSKTk
  • 0ed1fe018a924c38f667d14e72b5c76a0b9b23d1aa
  • 40lagp4hv68edoct8ma22dp01o
  • v2i0njmr7pm8t9qkn6d21aoaiv
  • mkno75ttagievjn6rg3n2kdur5
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