rka.build

Valid Email Server

Domain Overview

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

Checked via [email protected] · 2026-03-19 08:37:34 UTC · ↺ Refresh

MX Hostnames

  • rka-build.mail.protection.outlook.com

MX Priorities

  • rka-build.mail.protection.outlook.com: 10

A / AAAA Records

  • 134.209.218.207 ↩ 917166.cloudwaysapps.com

Mail Server IPs

  • 52.101.42.18 ↩ mail-co1pr03cu00302.inbound.protection.outlook.com
  • 52.101.40.2 ↩ mail-cy1pr05cu00402.inbound.protection.outlook.com
  • 52.101.9.21 ↩ mail-bl2pr04cu00205.inbound.protection.outlook.com
  • 52.101.11.13 ↩ mail-sn1pr0501cu00205.inbound.protection.outlook.com
  • 2a01:111:f403:f90b:: ↩ mail-bn6pr04cu00100.inbound.protection.outlook.com
  • 2a01:111:f403:f909:: ↩ mail-bn6pr04cu00200.inbound.protection.outlook.com
  • 2a01:111:f403:f901:: ↩ mail-mn2pr04cu00200.inbound.protection.outlook.com
  • 2a01:111:f403:f908:: ↩ mail-bn1pr21cu00100.inbound.protection.outlook.com

SOA Record

Raw SOA ns63.domaincontrol.com dns.jomax.net 2024110700 28800 7200 604800 600
Primary NS (mname)
ns63.domaincontrol.com
Admin Email (rname)
dns@jomax.net
Serial
2024110700
Refresh
28800s
Retry
7200s
Expire
604800s
Minimum TTL
600s

Nameservers (NS)

ns64.domaincontrol.com
ns63.domaincontrol.com

SPF Record

✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com include:spf.sendinblue.com mx -all
📊 DNS lookups: 3/10
✓ Hard fail (-all) — strict enforcement

DMARC Record

✗ p=none
v=DMARC1; p=none;
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed · DKIM alignment: Relaxed
⚠ No aggregate reports (rua= not set)

DKIM Selectors

✓ 1 found
mail._domainkey
✓ Public key: 216 chars (valid)
✓ DKIM properly configured for selector: mail

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

All TXT Records

5 records
  • google-site-verification=_QOJN_kbbyzby33MuJyrZb_-W_J7G9NeXDTGBk3xBI0
  • google-site-verification=DzIiHdRqVF-nntmylexykqE4bMo9TldftswFbDe7DrQ
  • SPFv=spf1 include:spf.protection.outlook.com include:spf.sendinblue.com mx -all
  • MS=ms20826343
  • sendinblue-code:12d1695b0b22a0aa2c40b9757e37ed50
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