Re: postfix as spam filtering server

7 msg	question on body_checks
7 msg	[Fwd: Re: postfix as spam filtering server]
2 msg	sender restrictions
3 msg	at what stage is message_size_limit applied?
6 msg	pipe and crashing commands

postfix as spam filtering server
\ Suhaime Raeze (13 May 2007)
. \ (Wietse Venema) (13 May 2007)
. . \ Suhaime Raeze (14 May 2007)
. . \ Suhaime Raeze (14 May 2007)
. . . \ Gaël Lams (14 May 2007)

3 msg	send mail to users on the same domain but a dif...
2 msg	Map several domains to virtual accounts ?
11 msg	postfix and MySQL encrypted passwords (was 554 ...
37 msg	tcp_table query.
2 msg	Last word on epoll and Slackware 11
5 msg	Open relay by forwarding loop?
3 msg	virtual subdomains
3 msg	reject_non_fqdn_sender and reject_non_fqdn_reci...
2 msg	'554 Recipient address rejected: Relay access d...
14 msg	Bounces, stopping them entirely
1 msg	Postfix mailing list administrivia
11 msg	postfix dropping SMTP connection when receiving...
8 msg	verify.db and reject_unverified_recipient
5 msg	proxymap query

Subject:	Re: postfix as spam filtering server
Group:	Postfix-users
From:	Gaël Lams
Date:	14 May 2007

Hi,

> question: is the setting of the firewall is the fault? or is there any
> setting that smtp authentication should be directed to the qmail server

Actually the classical way of doing what you are trying to do is to
configure the SMTP Auth directly on your postfix gateway, instead of
"forwarding" the smtp authentication to your qmail server (I don't
even know if it's possible).

I immagine that you have some kind of backend (ldap, mysql, ...)
containing username and password. You have to configure SASL to
perform the authentication on your backend and then configure postfix
to use sasl. Once the external user is authenticated, he/she can send
email through the postfix server.

> PS..both postfix and qmail are NAT to the same MX ip address

I'm not sure to understand this last sentence: normally, when you
set-up an smtp gateway (i.e often as an anti-spam filter), you do it
to avoid having your internal mail server directly accessible from the
outside, normally the 2 servers are separated boxes with separated ip
addresses, and the internal email server does not have a public ip
address.

Regards,

Gaël