Marc Powell wrote:
>
>>-----Original Message-----
>>From: centos-bounces@xxxxxxxxxx [mailto:centos-bounces@xxxxxxxxxx] On
>>Behalf Of Barry Brimer
>>Sent: Wednesday, June 29, 2005 9:47 AM
>>To: centos@xxxxxxxxxx
>>Subject: 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.
That is not quite true. Spammers will try the A records to send spam.
Not that much, but they will.
>
> Have you looked through the postfix wiki, documentation, faq, mailing
> list, etc? That'd be the first place I'd go since they _are_ the postfix
> experts ;).
>
> --
> Marc
