Graham Leggett:
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> Hi all,
>
> I have a machine that is both a postfix mailserver, and a NAT router for
> a number of machines behind the box.
>
> Because traffic from machines behind the box can cause the mailserver's
> IP to be blacklisted, the mailserver machine has two IP addresses, one
> for the mailserver, and one for NAT.
>
> There is a problem: postfix seems to be hell bent on choosing the NAT IP
> address as a source IP for outgoing connections, instead of the IP
> address specified by inet_interfaces:
>
> inet_interfaces = $myhostname
>
> According to the docs at http://www.postfix.org/postconf.5.html, "When
> inet_interfaces specifies just one IPv4 and/or IPv6 address that is not
> a loopback address, the Postfix SMTP client will use this address as the
> IP source address for outbound mail"
>
> This doesn't seem to be happening. Instead, postfix wants to choose the
> other IP address (which happens to be the NAT address) on the interface,
> rather than IP address @myhostname, which is the first IP on the interface.
>
> Can anyone confirm whether setting the source address in postfix is even
> possible, and how to force postfix to use a specific IP as a source address?
>
> I am using postfix-2.3.3-2 as shipped with RHEL5.
Prove it. Show actual evidence, instead of an eyewitness report.
Wietse
