MX records for email: Crawl Audit check 160

Short answer: MX records tell the world which servers accept email for your domain. Check 160 is informational and always passes: it reports how many MX records you have, or notes that the domain doesn't take email.

What Crawl Audit checks

• Pass: MX records found. The report shows how many.
• Pass: none, with a note that the domain doesn't handle email.

The count also feeds check 158: a domain with no MX records isn't expected to have DKIM.

What the standards say

• RFC 5321: a sending server "first attempts to locate an MX record associated with the name." On priority: "Lower numbers are more preferred than higher ones."
• RFC 5321 also says that with no MX record, mail falls back to the domain's own address. So "no MX" doesn't quite mean "no email".
• RFC 7505 gives a clear way to say a domain takes no mail: "a single MX RR" with priority 0 and a target of ".".

Getting them right

• Use exactly the values your email provider gives you, usually two or three servers with different priorities.
• For a domain that never receives mail, such as a campaign domain, publish a null MX and an SPF of v=spf1 -all so it can't be used for spoofing either.

example.com.  IN  MX  0  .

On devmarde.com

We have three MX records, all pointing at Zoho Mail with priorities 10, 20 and 50. It passes.

Sources

• IETF, RFC 5321: SMTP (October 2008) and RFC 7505: Null MX (June 2015), checked 6 October 2026.