I have built two test, temporary, mail servers to try out and test
configuration changes to our current system.
At the moment, the two server configs are the same, the only difference
between then two sets of /etc/exim4.conf and /etc/init.d/conf is the entry
primary_hostname
However, one mail server appears to work well, the second works locally,
but on receipt of mail from a remote server generates errros. The
senders (remote) maillog shows
550-Verification failed for <send_details>\n550-Unknown user\n550 Sender
verify failed
and local maillog records Unknown user+Sender verify failed.
Does anyone have an idea what is happening? I have a feeling that it is
related to hostnames (A and C records) but this is a guess.
