Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
theonsitegroup.co.uk
Yes
✓ Yes
Barracuda
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-29 08:00:35 UTC · ↺ Refresh
MX Hostnames
- d217700.b.ess.uk.barracudanetworks.com
- d217700.a.ess.uk.barracudanetworks.com
MX Priorities
- d217700.b.ess.uk.barracudanetworks.com: 99
- d217700.a.ess.uk.barracudanetworks.com: 99
A / AAAA Records
- 185.151.30.136 ↩ 185-151-30-136.ptr4.stackcp.net
- 2a07:7800::136 (no PTR)
Mail Server IPs
- 18.133.136.188 ↩ mail.ess.uk.barracuda.com
- 18.133.136.186 ↩ mail.ess.uk.barracuda.com
- 18.133.136.187 ↩ mail.ess.uk.barracuda.com
SOA Record
Raw SOA
ns1.stackdns.com hostmaster.stackdns.com 1765814627 1800 900 1209600 300
Primary NS (mname)
ns1.stackdns.com
Admin Email (rname)
hostmaster@stackdns.com
Serial
1765814627
Refresh
1800s
Retry
900s
Expire
1209600s
Minimum TTL
300s
Nameservers (NS)
ns3.stackdns.com
ns2.stackdns.com
ns4.stackdns.com
ns1.stackdns.com
SPF Record
✓ Soft Fail (~all)
v=spf1 include:spf.protection.outlook.com include:spf.exclaimer.net include:spf.ess.uk.barracudanetworks.com include:_spf.bullhornmail.com ip4:185.151.30.136/32 include:spf.rsmemployerservices.co.uk ~all
📊 DNS lookups: 5/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none; fo=1; rua=mailto:[email protected]; ruf=mailto:[email protected]
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 2 found
s1._domainkey
s2._domainkey
✓ Public key: 392 chars (valid)
✓ DKIM properly configured for selector: s1
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
3 records- SPFv=spf1 include:spf.protection.outlook.com include:spf.exclaimer.net include:spf.ess.uk.barracudanetworks.com include:_spf.bullhornmail.com ip4:185.151.30.136/32 include:spf.rsmemployerservices.co.uk ~all
- uaf82vo62oeu5qfuoh1hjorhgh
- MS=ms57794509
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