I have software with a newsletter system - but because I have 16 clients per server they are currently all sending emails from the same (eth0) IP address DESPITE having a DEDICATED ip address per client account for their WEB address.
If one spams (or gets spam complaints) then they all suffer - and I'd love to send their email via their unique IP address to stop this problem and to make the IP match their domain which has to be better at getting through spam filters anyway I'd have thought...

Any thoughts welcome - I've googled it for days with no answers - not even sure if it CAN be done.

All the best to you all,

Regards,
Rich.

not sure about sendmail or postfix, but exim with virtual domains can do something similar
then you can configure a config file for each virtual domain, and tell it how/where to route email in the route section

there are some examples here

http://www.tgunkel.de/docs/exim_smarthosts.en

but even better ones at http://www.exim.org/

What mail system are you using? Any answer is going to be specific to your program.

Hi,

how about the DNS server that serves your MX record? If you manage your own domain, you can change the MX record whatever you want.
If you manage the MX record, you would filter the accounts before/after sending mails.

Or another possibility to filter them is use Smart_Host. Forward all letters to a local spam filter system (spam-filter-gateway) then when they filtered the gateway will send them for the proper addresses.
One spam filter server could do the job. For example mail-scanner. http://mailscanner.info/

I used it for 4 domain filtering and one of the best spam filter system out there I think.

Laz.

I think his issue is outbound emails all going through a single public IP address.

exim can route emails to different mailserver ips....
just make sure you configure exim to listen on all these ips....and give different configs for each user.
assuming you are using or want to use exim

thanks everyone, exim does sound like the route to take then!

To answer someone elses question regarding what software I'm using...
I'll use whatever software is CAPABLE of doing it - there's no point me saying "I'm using sendmail" if sendmail can't do it... if you see what I mean...

We have centos on the box, and I'd have trouble getting rid of that for another OS - but otherwise I'll install anything that sorts the problem.

Thanks again all!

Rich.