Hello Nataniel,

Oh, I forgot... To make postfix use dbmail's aliases table for local
addresses, add to main.cf:

local_recipient_maps = mysql:/etc/postfix/mailbox.cf

where mailbox.cf contains the parameters for checking an address
against the dbmail aliases table, such as:

user = postfix
password = password
dbname = dbmail
table = aliases
hosts = 192.168.2.2
select_field = alias
where_field = alias

Reload postfix, any any address or user that is in your dbmail system
will be considered "local" by postfix, and non-existant addresses will
bounce before getting turned over to dbmail.

FAILING to do this lets your system be an open relay, using a trick
that works nearly 100% with Lotus Notes, Exchange Server, and
Groupwise, i.e., the bounce-relay.

That works by sending a message "from" the target, to a non-existant
address on a mail server. The above-named servers will accept mail to
their domain, THEN check to see if the user exists. If the user
doesn't exist, the message is then "bounced" to the return address,
with the original message as an attachment.... which was the original
target of the spam.

By bouncing the message before it is accepted, you don't get this
hole.

-- 
Jeff Brenton
President,
Engineered Software Products, Inc
http://espi.com
Questionable web page: http://dididahdahdidit.com

Liberalism grants you the freedom to advocate any idea*.
 * Please see http://www.dididahdahdidit.com/except.php for a
   current list of exceptions

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