These are the contents of '/etc/aliases' file on my Debian (Wheezy) server, as it is:
# /etc/aliases mailer-daemon: postmaster postmaster: root nobody: root hostmaster: root usenet: root news: root webmaster: root www: root ftp: root abuse: root noc: root security: root root: t
1. I noticed that, by default, my server sends email from what looks like
email@example.com. So, which one of the rules above governs this?
2. So, the rules in '/etc/aliases' are used to assign users to specific departments? That is, for example, all emails to be sent/received for 'abuse' will be delivered from/to firstname.lastname@example.org (which'd be the default email for root, unless there's an alias). Correct?
3. Can someone please explain what each of these really meant for -- mailer-daemon, postmaster, nobody, hostmaster, usenet, news, webmaster, www, ftp, abuse, noc, security, root?
I mean, a description like "
mailer-daemon for sending email delivery errors, but not really meant for receiving emails.
security for where people should contact your about security issues", or something like that.
As obvious as it should be by now, this is a newbie question. So, please try to be as clear as possible.