The https://first2host.co.uk/blog/install-exim-email-and-dovecot-on-ubuntu-and-debian-servers/ Diaries
You can find the settings related to simple textual content authentication in The ten-auth.conf file. This file incorporates a line (and that is commented out by default) that reads:7. Virtual Aliases During this table we are going to add every one of the emails that will be forwarded to a different email.The Dovecot installation procedure automati