Fix: 'config error: mail loops back to me (MX problem?)'
To prevent receiving
config error: mail loops back to me (MX problem?) errors, you need to add each
virtualdomain.tld to the
/etc/mail/local-host-names file and re-compile your sendmail config via
You have asked mail to a domain (e.g., domain.net) to be forwarded to a specific host (in this case, relay.domain.net) by using an MX record, but the relay machine doesn't recognise itself as domain.net. Add domain.net to /etc/mail/local-host-names [known as /etc/sendmail.cw prior to version 8.10] (if you are using FEATURE(`use_cw_file')) or add "Cw domain.net" to your configuration file.
Perform the following to enable email forwarding from the virtual domain
virtualdomain.tld to another email address (in this example, email@example.com). There are no local accounts associated - the aliases file has been left untouched.
Note that the
hostname of the system this was performed on is different to
virtualdomain.tld; typically, this should be the case for you as well (that's the whole point of virtual hosts;
default will be bound to whatever VPS provided access domain defined in
# Hosts with to allow relaying virtualdomain.tld RELAY
Remove ", Addr=" clauses to receive from any interface. Do this with caution as this opens up your MTA to be abused by spammers if you're not careful.
/etc/mail/access needs to be setup carefully to ensure it rejects any domains apart from your own.
dnl DAEMON_OPTIONS(`Family=inet6, Name=MTA-v6, Port=smtp, Addr=::1')dnl DAEMON_OPTIONS(`Family=inet, Name=MTA-v4, Port=smtp')dnl
Add the following
dnl # Define virtualusertable FEATURE(`virtusertable', `hash /etc/mail/virtusertable')dnl VIRTUSER_DOMAIN_FILE(`/etc/mail/virtual-domains')dnl
virtusertable and add
/etc/init.d/sendmail reload to restart the daemon. You can debug the relaying action by watching the log file by doing
tail -f /var/log/mail.log.