Directing your mail.
WHAT THEY DO
Specify which servers accept mail for your domain.
Without them, mail to your domain fails.
WHAT THEY CONTAIN
A hostname, not an address. Usually mail.yourdomain.com.
And a priority number.
THE PRIORITY
Lower numbers are tried first. A single MX record with priority 0 or 10 is normal for most hosting.
Multiple records with different priorities provide fallback.
THE HOSTNAME MUST RESOLVE
An MX record pointing at a hostname with no A record does not work.
If your MX points at mail.yourdomain.com, that name needs an A record.
WHAT CPANEL EXPECTS
cPanel > Email Deliverability shows what your records should be. Compare against what is published.
LOCAL VERSUS REMOTE MAIL
cPanel has a setting determining whether mail for the domain is delivered locally or sent to the MX records.
If you use external mail, that must be set to remote, or mail stays on the server and never reaches the external provider.
That setting is the cause of a specific confusing failure: MX records correct, mail still not arriving at the external provider.
NEVER PROXY THEM
At Cloudflare, mail records must be DNS only.
