I will be using my Linode VPS to host a decent number of client websites, and offering Google Apps email services for any client's email needs.

I have configured the DNS to use Google Apps correctly and this is pretty straight forward, but I am having trouble getting a SMTP configuration working so that, when managing a collection of email address from a single Gmail account, it will not send 'On Behalf Of...'

The set up for this within Gmail requires SMTP authentication from my server.
Currently I am able to use PHPMailer on my server (does this mean it must already have Postfix, or similar, already installed? I used a StackScript to install Unbuntu 10.04.2 LTS), but still need assistance in configuring my server to handle this SMTP requirement.

I have looked at the tutorials here: http://library.linode.com/email/postfix/ but not sure if any of these are appropriate.

tl;dr: I do not require email features, Google Apps handles this, just need SMTP functionality to send mail from Gmail via Linode server.


Thanks in advance for any assistance

To send via google apps you don't need postfix check out http://msmtp.sourceforge.net/index.html

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