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
