On 1/11/2010 1:00 PM, brian moore wrote:
On Mon, 11 Jan 2010 15:27:05 -0300
"Damian Rivas"<dam...@cht.com.ar> wrote:
Hello everyone,
I have a Postfix box basically configured to send mail from my organization to
the Internet. Today I received a warning message telling me that the mail queue
was full.
It seems that some Spammer is using my server as an Open Relay, so I used the
"check_sender_access" function to only allow my domains to send mail to the
outside, but it is not working and I don't know what to do, perhaps you can give me some
tips.
You seem to be allowing anyone forging one of your domains to relay.
That is not good.
smtpd_sender_restrictions = permit_mynetworks,
check_sender_access = hash:/etc/postfix/sender_map,
reject_non_fqdn_sender, reject_unknown_sender_domain, permit
That 'check_sender_access' is evil. Please remove it.
Replace it with:
reject_unauth_destination
Damian,
Please ignore the above bad advice. An OK in
smtpd_sender_restrictions can not possibly make you an open
relay. Likely it didn't work as expected because the mail
isn's submitted via SMTP.
Before you waste time on any other bad advice you may get,
examine your logs to see where the mail comes from. Once you
know the problem, a solution is much easier.
Post logs here if you don't know how to evaluate them.
My wild guess is that you have an abused web form, but check
the logs before you go running around telling everyone your
web server is hacked.
-- Noel Jones
