received mail from Internet ==> L4 ==> private postfix ==> L4 ==> deliver to internet
postfix will write "hostname" in "received by" field and "remote hostname and IP" in "received from" field. That's fine for incoming mail from internet. (you can use a proper hostname for your postfix) For outgoing mail, your MTA(Postfix) MUST contain valid public IP, otherwise your mail will be rejected by other MTA. However, you still can use port forwarding on L4. If you support TLS, take care of your certificate file which must match your domain. Regards, King 2013/8/16 Thomas Herrmann <therrm...@adwin.de> > Hello Postfix-users, > > currently, I have two postfix servers running for my domain: > - one on a physical server with a single, public IPv4 address (and > proper DNS setup) that just accepts mails and delivers them to > - the second one in my private LAN (where mails are delivered locally to > the imap server). > > This setup has various disadvantages, so I am thinking about about the > following setup: > > Only one postfix in my private LAN, with a VPN connection to the public > server, and some port forwardings so that my private postfix > installation "appears" to run on the public IP address. > > Are there any known problems with this setup? I think it will probably > just work, but I am afraid of private IP addresses showing up in mail > headers that might trigger some spam detection mechanisms, or other > non-obvious issues. Does postfix write its own, local IP address into > outgoing mail? Should the last "received by" header of my outgoing mail > match with the IP/hostname I am sending the mail from? > > Regards, > Thomas Herrmann >
