Aliases allow you to have an infinite number of valid recipient addresses on your system, and you don’t have to worry about creating accounts or other support files for each address. For example, most systems have “postmaster” defined as a valid recipient but do not have an actual login account named postmaster. Aliases are configured in the file
/etc/aliases. Here is an example of an alias entry:
This entry forwards any mail received for postmaster to the root user. By default, almost all the aliases listed in the
/etc/aliases file forward to root.
Reading email as root is a security hazard; a malicious email message can exploit an email client and cause it to execute arbitrary code as ...