Postfix user and mailbox aliases

An easy way to redirect email from a user account to another user account in Postfix is using aliases.
For example if we need to redirect all email destined for the user g to the mailbox of the user rootie we could add the following line to /etc/aliases and then run newaliases.

The /etc/aliases:
~#cat /etc/aliases
# /etc/aliases
g: rootie


Recreate the /etc/aliases.db Berkley DB hash used by Postfix
#newaliases


Test:
ares:~#mail g
Cc: 
Subject: this is for rootie through g
 testin testin 1 2 3 rootie
.
#su rootie
rootie$ cat ~/Maildir/new/1338216976.Vfb00I6f088M939772.ares
Return-Path: 
X-Original-To: g@ares
Delivered-To: g@ares
Received: by ares.ipduh.com (Postfix, from userid 0)
 id DF78E4AC77; Mon, 28 May 2012 14:56:16 +0000 (UTC)
To: 
Subject: this is for rootie through g
X-Mailer: mail (GNU Mailutils 2.1)
Message-Id: <20120528145616.DF78E4AC77@ares>
Date: Mon, 28 May 2012 14:56:16 +0000 (UTC)
From: root@ares.ipduh.com (root)

 testin testin 1 2 3 rootie
$ exit
#


Note: To send the email, exit the mail program, and get back to command prompt when sending an email from the command line use CTRL-D

OK. What about redirecting virtual mailboxes on multiple domains to the same unix account?

Upon setting the MX records for these domains add them on mydestination and virtual_alias_domains in /etc/postfix/main.cf
# cat /etc/postfix/main.cf | egrep 'mydestination|virtual_alias_domains'
mydestination = ares.ipduh.com , ipduh.net , ipduh.org , ip.duh.gr , ares , localhost
virtual_alias_domains = ares.ipduh.com ipduh.net ipduh.org ip.duh.gr
Then we need to set the path to the hash we will use in /etc/postfix/main.cf
# grep virtual_alias_maps /etc/postfix/main.cf 
virtual_alias_maps = hash:/etc/postfix/virtual
/etc/postfix/virtual looks like:
# cat /etc/postfix/virtual
someone@ares.ipduh.com     rootie
another@ipduh.net          rootie
bingo@ipduh.org            rootie
bogo@ip.duh.gr             rootie


Finally we need to create the Berkeley DB Hash used by Postfix when mapping virtual mailboxes and maybe restart Postfix.
# postmap /etc/postfix/virtual
# /etc/init.d/postfix restart
Stopping Postfix Mail Transport Agent: postfix.
Starting Postfix Mail Transport Agent: postfix.


Done!



Postfix user and mailbox aliases