Hello,

I want to configure postfix to make it able to send emails from different IP addresses (all of them bound on one server). Right now I have a working postfix+courier+sasl, but I need it to send the email from the IP that it receives the connection.
For example:
There are 3 ip addresses bound on a 3 virtual interfaces (192.168.10.1 .2 and .3). When a user tries to send an email connecting to 192.168.10.3, is it possible for postfix to send the email from that IP (not from .1 or whatever the physical interface is)?

I know this is possible by creating clones (with small config modification) of postfix, but this won't do the job for me since I want to install aprox 200 of this interfaces. I'm running (the company that I work for) a website with fashion campaigns and it sends more than 50K emails each day, 90% of them being hosted by Yahoo (all users being registered, so this is not spam) and I'm sure that you are aware of Yahoo's policies. I tried to use throttling solutions (send 2 emails per second or even less), the messages are still deferred after some time. So my last option before buying some service from inxmail or mailchimp is to try this, but I cannot implement it (google is not my best friend in this case).

Did someone made it work? If yes, can you give me a tip (I'm not asking for the full solution).

Thank you and please excuse my english

Yahoo has these policies in place for a reason. I would suggest working with yahoo to become white listed as a bulk sender. If the mail is legitimate, then their should be no reason that some sort of agreement couldn't be worked out. Subverting their deferral solution will only lead to stricter deferral policies being put in place. If I noticed high amounts of the same mail coming from different IP's from a particular subnet I would just blacklist the entire CIDR range that was allocated to the AS.

I know some of the large mail houses (aol, yahoo, hotmail, etc..) may be difficult to initially work with. You could try to get their users to contact them on your behalf. If enough of their users complained that the mail you send them isn't being delivered they would probably be more willing to work with you. Otherwise you'll spend the time coming up with an elaborate solution that sends mail on multiple interfaces and in a few keystrokes it all will be blocked again (in fact, its probably automated). If they report to other blacklists the problem will then compound because anyone using spamhaus, njabl, etc.. won't accept connections from your IP's either.

If the mail is legitimate good luck. If not, find another way to make money.

Thank you, I will try to contact them again (hope this time I won't get back into a loop with their answering robot). For sure the email is legitim and also all users that are receiving are registered (and accepted the terms and condition where is specified that will receive an email on every campaign). The problem is that romanian users instead of just deleting the email or unsubscribe the newsletter, they mark it as spam.

PS: not everybody in romania is a scammer