c1s.net

Valid Email Server

Domain Overview

DNS: ✓ 2mo ago Checker: ✓ 2mo ago
c1s.net
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]

Checked via [email protected] · 2026-03-24 00:41:02 UTC · ↺ Refresh

MX Hostnames

  • c1s-net.mail.protection.outlook.com

MX Priorities

  • c1s-net.mail.protection.outlook.com: 0

A / AAAA Records

  • 104.21.8.119 (no PTR)
  • 172.67.139.109 (no PTR)
  • 2606:4700:3034::ac43:8b6d
  • 2606:4700:3030::6815:877

Mail Server IPs

  • 52.101.9.2 ↩ mail-mn2pr02cu00202.inbound.protection.outlook.com
  • 52.101.9.12 ↩ mail-bl0pr05cu00504.inbound.protection.outlook.com
  • 52.101.50.10 ↩ mail-mw2pr02cu00502.inbound.protection.outlook.com
  • 52.101.50.7 ↩ mail-co1pr21cu00207.inbound.protection.outlook.com
  • 2a01:111:f403:c901::1 ↩ mail-bl2pr04cu00201.inbound.protection.outlook.com
  • 2a01:111:f403:f802::1 ↩ mail-sj2pr05cu00101.inbound.protection.outlook.com
  • 2a01:111:f403:c902::2 ↩ mail-sj0pr03cu01602.inbound.protection.outlook.com
  • 2a01:111:f403:f902:: ↩ mail-bl2pr04cu00100.inbound.protection.outlook.com

SOA Record

Raw SOA dee.ns.cloudflare.com dns.cloudflare.com 2396476656 10000 2400 604800 1800
Primary NS (mname)
dee.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2396476656
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s

Nameservers (NS)

dee.ns.cloudflare.com
vick.ns.cloudflare.com

SPF Record

✓ Soft Fail (~all)
v=spf1 include:spf.protection.outlook.com include:mxlogic.net include:servers.mcsv.net include:sendgrid.net ~all
📊 DNS lookups: 4/10
~ Soft fail (~all) — moderate enforcement

DMARC Record

✗ p=none
v=DMARC1; p=none; pct=100; rua=mailto:[email protected]; sp=none; aspf=r;
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed · DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
↳ Subdomain policy: none

DKIM Selectors

✓ 3 found
k1._domainkey
s1._domainkey
s2._domainkey
✓ Public key: 216 chars (valid)
✓ DKIM properly configured for selector: k1

Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses

All TXT Records

3 records
  • MS=ms76119845
  • SFMC-E7PWB7rLlKdUL659R12hie4CWHwmjJqL24V8C8Lo
  • SPFv=spf1 include:spf.protection.outlook.com include:mxlogic.net include:servers.mcsv.net include:sendgrid.net ~all
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