Dovecot is a POP3 and IMAP server free and open-source that can act as a mail storage server. It is used to deliver and retrieve emails to and from local mailboxes.

Crear usuario virtual

sudo vi /etc/postfix/virtual root

sudo postmap /etc/postfix/virtual

sudo postfix reload

Añadir en Postfix

virtual_alias_maps = hash:/etc/postfix/virtual
virtual_alias_domains = hash:/etc/postfix/virtual_domains

Instalar Dovecot

sudo apt install dovecot-imapd