Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
certn.co
Yes
✓ Yes
Google
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-30 13:21:23 UTC · ↺ Refresh
MX Hostnames
- aspmx.l.google.com
- alt4.aspmx.l.google.com
- alt3.aspmx.l.google.com
- alt1.aspmx.l.google.com
- alt2.aspmx.l.google.com
MX Priorities
- alt3.aspmx.l.google.com: 10
- alt4.aspmx.l.google.com: 10
- alt1.aspmx.l.google.com: 5
- alt2.aspmx.l.google.com: 5
- aspmx.l.google.com: 1
A / AAAA Records
- 172.66.40.146
- 172.66.43.110
Mail Server IPs
- 192.178.223.27 ↩ yulhrs-in-f27.1e100.net
- 2a00:1450:4009:c0f::1b ↩ yulhrs-in-f27.1e100.net
- 173.194.76.27 ↩ ws-in-f27.1e100.net
- 2a00:1450:400c:c00::1a ↩ ws-in-f26.1e100.net
- 108.177.123.27 ↩ lcscld-in-f27.1e100.net
- 2800:3f0:4003:c0f::1b (no PTR)
- 172.253.116.26 ↩ dj-in-f26.1e100.net
- 2a00:1450:400b:c02::1b ↩ dj-in-f27.1e100.net
- 172.253.122.27 ↩ bh-in-f27.1e100.net
- 2607:f8b0:4004:c1b::1a ↩ wv-in-f26.1e100.net
SOA Record
Raw SOA
bob.ns.cloudflare.com dns.cloudflare.com 2400174376 10000 2400 604800 1800
Primary NS (mname)
bob.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2400174376
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s
Nameservers (NS)
reza.ns.cloudflare.com
bob.ns.cloudflare.com
SPF Record
✓ Strict (-all)
v=spf1 include:_spf.google.com include:_spf.atlassian.net include:spf.tipalti.com include:mail.zendesk.com include:22400366.spf01.hubspotemail.net include:credence.co.uk include:spf.trustifi.com -all
📊 DNS lookups: 7/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none; pct=100; rua=mailto:[email protected],mailto:[email protected]; sp=reject; aspf=r;
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected],mailto:[email protected]
↳ Subdomain policy: reject
DKIM Selectors
✓ 4 found
google._domainkey
k1._domainkey
s1._domainkey
s2._domainkey
✓ Public key: 392 chars (valid)
✓ DKIM properly configured for selector: google
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
21 records- atlassian-sending-domain-verification=bc053f07-d208-4be6-b7ef-0258939c7129
- slack-domain-verification=ZYnCDWrLRiFMDoDUUuGovvxRnh2wN4cN01T5s2Op
- lovable_verification=workspace_01k601veeqfxjajcc88jvbgx99
- atlassian-domain-verification=NnJReYkZk2KgNDLWLea6t1p2mPSnH2w04QV78mTvG1av0SzuShdcz03McIHGBOhh
- apple-domain-verification=QMj0hOTRJf6L0akB
- ca3-98000bdabe9c468b95a50a003a7241e4
- google-site-verification=2Mu1iHY4snU-ErRLWHkG7zf46t7V7jgUbdwT56VtNeU
- SPFv=spf1 include:_spf.google.com include:_spf.atlassian.net include:spf.tipalti.com include:mail.zendesk.com include:22400366.spf01.hubspotemail.net include:credence.co.uk include:spf.trustifi.com -all
- notion-domain-verification=teavVfVoP0g0Q8NvUdkZdD7DtrVwahgPX30wxjQ3WrW
- pendo-domain-verification=b2dba1e9-34de-4428-bee1-35e9972af94f
- cursor-domain-verification-kta3m9=rKMDGpgE1Mx9P4wir2XglLIi1
- google-site-verification=PeErWhWhXC27ky0jZG3i-Kdp8Dtv_1Vc9-7FvrumPqc
- google-site-verification=knKR4ugNqHCafmhG6WvDFDptx_-1hITNYQEhFRI1j0I
- 76ee236f50a176979c9039eb0ad80ae3bd77ae13dcdf87410ec1a33a01d6ecc8
- google-site-verification=mAyTK2P2ug3ynzS78kHIgu3ORASwNqQLN9f1FJQbkbw
- miro-verification=0eb3f69ee5a0a7da88c50f3a935803491ebb124a
- drift-domain-verification=636b8969144ef5c9f4ab33eafcf096e8a7a11c0e98189c07e1d06b66b2a6bd78
- druide-validation-domaine=6939562318f81786dabd29c9a1376b63
- google-site-verification=1UDR33gqA8zE2csTUoBY-asVWqEEP8-5FUWsT1sSCtQ
- google-site-verification=RD4kKAB4uDgOY5XbF9V1bipz7JpLJ3yuCjR8I_WS_0U
- MS=ms21030883
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