I'm trying to configure a domain that has never accepted mail
from external sources to start. The server runs exim, which I've
never used. I send a message to the domain using its IP, for example
fred@123.456.789.012. exim returns:
'rejected RCPT : The mail server could not deliver mail to
'fred@123.456.789.012. The account or domain may not exist,
'they may be blacklisted, or missing the proper dns entries.'
dig mx 123.456.789.012
returns NXDOMAIN.
fred gets and sends mail locally (sends it to remote
addressees too), is not in the blacklist; 123.456.789.012 is a valid IP.
Why does the message get to exim if the MX domain doesn't
exist? Since it gets to exim, is it possible to get exim to ignore
the lack of a DNS entry for the domain and send fred the message? I
can't modify the DNS entry.