buf.build

Valid Email Server

Domain Overview

DNS: ✓ 10h ago Checker: ✓ 10h ago
buf.build
Yes
✓ Yes
Google
No
No
⚠ Yes
No
No
Did you mean: [email protected]

Checked via [email protected] · 2026-05-21 04:30:59 UTC · ↺ Refresh

MX Hostnames

  • alt3.aspmx.l.google.com
  • aspmx.l.google.com
  • alt2.aspmx.l.google.com
  • alt1.aspmx.l.google.com
  • alt4.aspmx.l.google.com

MX Priorities

  • aspmx.l.google.com: 1
  • alt3.aspmx.l.google.com: 10
  • alt4.aspmx.l.google.com: 10
  • alt1.aspmx.l.google.com: 5
  • alt2.aspmx.l.google.com: 5

A / AAAA Records

  • 34.95.71.106

Mail Server IPs

  • 172.253.63.26 ↩ bi-in-f26.1e100.net
  • 2607:f8b0:4004:c1f::1a ↩ pd-in-f26.1e100.net
  • 192.178.223.26 ↩ yulhrs-in-f26.1e100.net
  • 2a00:1450:4009:c0f::1a ↩ yulhrs-in-f26.1e100.net
  • 173.194.76.26 ↩ ws-in-f26.1e100.net
  • 2a00:1450:400c:c00::1b ↩ ws-in-f27.1e100.net
  • 108.177.123.27 ↩ lcscld-in-f27.1e100.net
  • 2800:3f0:4003:c0f::1a (no PTR)
  • 172.253.116.26 ↩ dj-in-f26.1e100.net
  • 2a00:1450:400b:c02::1a ↩ dj-in-f26.1e100.net

SOA Record

Raw SOA rosemary.ns.cloudflare.com dns.cloudflare.com 2401941023 10000 2400 604800 1800
Primary NS (mname)
rosemary.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2401941023
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s

Nameservers (NS)

rosemary.ns.cloudflare.com
tony.ns.cloudflare.com

SPF Record

✓ Soft Fail (~all)
v=spf1 include:_spf.google.com include:8423972.spf08.hubspotemail.net include:mg-spf.greenhouse.io ~all
📊 DNS lookups: 3/10
~ Soft fail (~all) — moderate enforcement

DMARC Record

✓ Reject
v=DMARC1; p=reject; pct=100; fo=0:1:s:d; rua=mailto:[email protected],mailto:[email protected]; ruf=mailto:[email protected]
✓ Reject — strongest protection
📋 SPF alignment: Relaxed · DKIM alignment: Relaxed
📧 Reports → mailto:[email protected],mailto:[email protected]

DKIM Selectors

✓ 1 found
google._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

16 records
  • MS=ms40326687
  • OSSRH-84676
  • ZOOM_verify_tNPqhddwpXox0zf4Eclck7
  • _gzlouu2guf68olrwwq0s94geej4ff12
  • anthropic-domain-verification-53edjt=MQ72mrdHu0iyqLC6hjd4sU3wZ
  • apple-domain-verification=uFHzTjAuMQqmvmeJ
  • cursor-domain-verification-nr2khg=zXW8kPNUhjs6YQg0xBjLj9pdB
  • google-site-verification=lycZSscFSeDJpzUM9BNZQgMEAiURSrjA12XxldAQsUA
  • jetbrains-domain-verification=dusacr8g1qgfavwytsodypi51
  • linear-domain-verification=358850
  • notion_verify_mVP?)],~n*mV_u1M@=rr_B7Hj1~4Mjc!s_0WD:}-TzY!h^M,#7Mae1^@Wdw}LbXtUQnxYR
  • pylon-domain-verification-9xp7sc=r7X9JwtzdrYACNG0xUu0cwF3l
  • stripe-verification=a0cfb5be3da0244c101501f2d4012739e163fa5ccda68b52f8a5b43246669441
  • stripe-verification=d9ddbc83e579b6d4807dca1abde8eb75e67fcd674034ce1fe339d69b9dead0f6
  • SPFv=spf1 include:_spf.google.com include:8423972.spf08.hubspotemail.net include:mg-spf.greenhouse.io ~all
  • B997BD242A
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