rsb.uk.com

Valid Email Server
Domain Lookup › rsb.uk.com

Domain Overview

DNS: ✓ 2mo ago Checker: ✓ 2mo ago
rsb.uk.com
Yes
✓ Yes
Barracuda
No
No
⚠ Yes
No
No
Did you mean: [email protected]

Checked via [email protected] · 2026-04-01 03:25:49 UTC · ↺ Refresh

MX Hostnames

  • d208329.a.ess.uk.barracudanetworks.com
  • d208329.b.ess.uk.barracudanetworks.com

MX Priorities

  • d208329.a.ess.uk.barracudanetworks.com: 5
  • d208329.b.ess.uk.barracudanetworks.com: 10

A / AAAA Records

  • 94.136.40.82 (no PTR)
  • 2a07:7800::171 (no PTR)

Mail Server IPs

  • 18.133.136.186 ↩ mail.ess.uk.barracuda.com
  • 18.133.136.188 ↩ mail.ess.uk.barracuda.com
  • 18.133.136.187 ↩ mail.ess.uk.barracuda.com

SOA Record

Raw SOA ns1.stackdns.com hostmaster.stackdns.com 1770822385 1800 900 1209600 300
Primary NS (mname)
ns1.stackdns.com
Admin Email (rname)
hostmaster@stackdns.com
Serial
1770822385
Refresh
1800s
Retry
900s
Expire
1209600s
Minimum TTL
300s

Nameservers (NS)

ns1.stackdns.com
ns4.stackdns.com
ns3.stackdns.com
ns2.stackdns.com

SPF Record

✓ Strict (-all)
v=spf1 ip4:193.117.135.250 ip4:77.68.10.168 include:spf.protection.outlook.com -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement

DMARC Record

~ Quarantine
v=DMARC1;p=quarantine;sp=none;adkim=r;aspf=r;pct=100;rf=afrf;ri=86400
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed · DKIM alignment: Relaxed
⚠ No aggregate reports (rua= not set)
↳ Subdomain policy: none

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

3 records
  • SPFv=spf1 ip4:193.117.135.250 ip4:77.68.10.168 include:spf.protection.outlook.com -all
  • MS=ms77843306
  • google-site-verification=nXVWjOHUo45s_yuBzujyYWsMM_AaGO3wAcC-jHsy4bI
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