File: //usr/share/webmin/postfix/help/opt_mydestination.html
<header>What domain to receive mail for</header>
<center><tt>mydestination</tt></center>
<hr>
You specify what domains this machine will deliver locally, instead of
forwarding to another machine. The default is to receive mail for the machine
itself.
<p>
<b>Local machine</b>: <tt>$myhostname, localhost.$mydomain</tt>
<br>
<b>Whole Domain</b>: <tt>$myhostname, localhost.$mydomain,
$mydomain</tt>
<p>
You can also specify the full path of a file, which will contain the names of
domains that this machine will deliver mail locally for.
<p>
Example: <tt>/etc/postfix/mydestination</tt>
<hr>
<br>
<b><u>Caution:</u></b> in order to avoid mail delivery loops, you must list all
hostnames of the machine, including <tt>$myhostname</tt>, and
<tt>localhost.$mydomain</tt>. DO NOT LIST VIRTUAL DOMAINS HERE. LIST THEM IN
THE VIRTUAL FILE INSTEAD.