Domain Overview
DNS: ✓ 20d ago
Checker: ✓ 20d ago
m4-engineering.com
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-05-20 23:05:08 UTC · ↺ Refresh
MX Hostnames
- m4-engineering-com.p20.spamhero.net
- m4-engineering-com.p30.spamhero.net
- m4-engineering-com.p10.spamhero.com
- m4-engineering-com.p40.spamhero.net
MX Priorities
- m4-engineering-com.p10.spamhero.com: 10
- m4-engineering-com.p20.spamhero.net: 20
- m4-engineering-com.p40.spamhero.net: 40
- m4-engineering-com.p30.spamhero.net: 30
A / AAAA Records
- 47.181.126.124 ↩ static-47-181-126-124.lsan.ca.frontiernet.net
Mail Server IPs
- 209.41.68.146 ↩ 209-41-68-146.ip.serverbox.net
- 216.172.106.29 ↩ bolt113a.mxthunder.net
SOA Record
Raw SOA
ns1.siteground.net admins.siteground.com 573 86400 7200 3600000 86400
Primary NS (mname)
ns1.siteground.net
Admin Email (rname)
admins@siteground.com
Serial
573
Refresh
86400s
Retry
7200s
Expire
3600000s
Minimum TTL
86400s
Nameservers (NS)
ns2.siteground.net
ns1.siteground.net
SPF Record
✓ Strict (-all)
v=spf1 +a +mx +ip4:35.208.165.164 include:spf.protection.outlook.com include:m4-engineering.com.spf.auto.dnssmarthost.net include:3851887.spf02.hubspotemail.net -all
📊 DNS lookups: 5/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1; p=quarantine; rua=mailto:[email protected];
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 3 found
selector1._domainkey
selector2._domainkey
default._domainkey
✓ Public key: 392 chars (valid)
✓ DKIM properly configured for selector: selector1
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
4 records- v=DMARK1; p=quarantine; rua=mailto:[email protected]; ruf=mailto:[email protected]
- MS=ms89106001
- MS=541326E4E2E37BF8ADAFA641F8B2B4B283C563E4
- SPFv=spf1 +a +mx +ip4:35.208.165.164 include:spf.protection.outlook.com include:m4-engineering.com.spf.auto.dnssmarthost.net include:3851887.spf02.hubspotemail.net -all
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