Marc Powell wrote: > >>-----Original Message----- >>From: centos-bounces at centos.org [mailto:centos-bounces at centos.org] On >>Behalf Of Barry Brimer >>Sent: Wednesday, June 29, 2005 9:47 AM >>To: centos at centos.org >>Subject: [CentOS] Postfix / Postini question >> >> >> >>I have a mail server that handles several domains. One of these > > domains > >>has >>decided to use Postini. For those not familiar with Postini, you set > > your > >>MX >>records to use their mail servers. They filter mail, and deliver you > > only > >>the >>clean virus/spam free mail. The idea is to only allow incoming mail > > from > >>their >>mail servers so spammers are unable to send to your mail server > > directly. > >>This >>is fairly simple to do with standard restriction classes for a > > dedicated > >>mail >>server. I am not sure how to accomplish this on a shared mail server. >>Ideally >>I would like to instruct postfix to accept mail from anywhere for all >>domains >>except one domain (the one using Postini) and only allow mail destined > > for > >>that >>specific domain to originate from Postini's mail servers. Any ideas > > would > >>be >>greatly appreciated. > > > > I'm not a postfix guru but I don't believe that is possible with a > shared server. However, it's been my experience that if your server is > not listed as an MX (and it won't), MXs exist (and they will -- > Postini's) then mail will not be delivered to your machine by anyone > except Postini. The only two scenarios I am aware of in which mail would > get delivered to your server instead of Postini's would be if a) you > were listed as a fallback MX or b) no MX's were specified then the A > record for your domain would be used. If you don't know, don't voice your opinions about postfix's abilities, please stay quiet. While, it would be rather rare for people to go to you direct when your servers are not listed in the MX...spammers however seem to manage to do that.