Changes

# On both machines, edit the '''/etc/postfix/main.cf''' file to change the '''myorigin''' parameter from '''$myhostname''' to '''$mydomain'''. Restart the '''postfix''' service.

# Now, send emails messages between both of your vm2 and vm3 machines. The sender address should now read that the received mail messages came from '''root@yourdomain.org'''.

The next step is to configure what addrssess the server will receive email for. This is done using postfix by setting the '''mydestination''' parameter (configuration variable) to include '''$mydomain''' (this is assuming you've set up '''mydomain''', '''myorigin''' , and '''inet_interfaces''' properly).