On Fri, Jan 17, 2020 at 10:02:28AM +0100, Jaroslaw Rafa wrote:
> It is a perfectly correct setup to not have an MX record for a domain,
> but to have an A record and receive email under that address.
So far so good...
> Instead of "u...@mailserver.domain.com" you type only
> "u...@domain.com" - that's what MX record is for. But
> "u...@mailserver.domain.com" is still perfectly valid and mail to such
> address *has to be* be delivered.
And here I'm afraid you've gone off the rails, there is no requirement
for example.com to accept email addressed to u...@mxhost.example.com,
whether or not mxhost.example.com is an MX host for the domain.
It is quite common for the "@example.com" addresses to be the only
externally valid addresses for users in a given domain. Email addresses
tend to linger in mailboxes for years, and it is not generally a good
idea to use or support addresses tied to specific hosts.
> I was recently forced to add a ridiculous MX record to my domain, pointing
> back to the same name (eg. "rafa.eu.org MX 10 rafa.eu.org") just to satisfy
> some stupid mailservers that used such approach and didn't send mail to me
> claiming my email address is "invalid".
And now back to reality, yes those other servers are broken. Plenty of
email domains have just A records. For some reason this is very popular
in Brazil, for example.
--
Viktor.
