Say you’re using sendmail to relay email on a web server that you own that’s named “domain.com”, and email is being delivered fine to any domain except domain.com. What could be the problem?
- Rename your server. No server should be named with an actual domain name.
- Change /etc/hostname to the new name for your server
- Update /etc/hosts to remove the domain name and replace with the new hostname
- Remove the domain name from /etc/mail/local-host-names
- Restart sendmail “sudo service sendmail restart”
- Restart your server “sudo reboot”
Once you’ve done that test sendmail out like so…
echo "command line test" | mail -s "Sendmail test" firstname.lastname@example.org