Robert Fitzpatrick a écrit : > I have an SMTP server down and would like to use another box > temporarily. The IP address of the down server is setup with reverse > DNS. I added this IP address as an alias to the interface on the temp > box, can Postfix control the IP used to send and allow me to use that > alias IP address when sending out so the reverse DNS will keep working? > Right now, it looks like mail is coming from the primary IP address of > the interface. And will this work for my purposes? >
do these 1- Take this as a lesson, and setup reverse dns for all of your IPs. so chose some names and use them. make sure reverse and forward match: 192.0.2.3 => foo.example.com foo.example.com => 192.0.2.3 note that the name identifies the IP, not the mail domain or anything. 2- use smtp_bind_address = 192.0.2.3 to set tell smtp to bind to this IP (smtp_bind_address6 if using IPv6). note that with this smtp will always use this IP (contrast with the default when smtp binds to "any address" and it is the routing code that selects the source IP based on the route (outgoing interface).
