sys.do

Valid Email Server
Domain Lookup › sys.do
Live data — DNS records and disposable check were just fetched and saved.

Domain Overview

DNS: ⚡ live Checker: ⚡ live
sys.do
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]

Checked via [email protected] · 2026-05-22 22:15:12 UTC · ↺ Refresh

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MX Hostnames

  • sys-do.mail.protection.outlook.com

MX Priorities

No priority data.

A / AAAA Records

  • 198.49.23.145
  • 198.185.159.144
  • 198.185.159.145
  • 198.49.23.144

Mail Server IPs

No IPs resolved.

SOA Record

No SOA record found.

Nameservers (NS)

ns1.bdm.microsoftonline.com
ns2.bdm.microsoftonline.com
ns3.bdm.microsoftonline.com
ns4.bdm.microsoftonline.com

SPF Record

✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement

DMARC Record

✗ Missing

No DMARC record — emails cannot be rejected on auth failure.

DKIM Selectors

✗ None detected

No 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

2 records
  • SPFv=spf1 include:spf.protection.outlook.com -all
  • mscid=bRXehd8AHPDv1rs2uqbzakqcOw14yzOPJx8qscAaG+v7Zfmra4TW/ob3Ok9YxySYmasg1fWQeNg0WxHeT+bayw==
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