Greetings! I have 3 servers connected via lan & vpn.
SERVER-1 is a hosted VM in the cloud EXTIF eth0 (198.51.100.1, 198.51.100.2, 10.0.1.1) TUNIF tun1 (192.168.1.1) SERVER-2 is my LAN's router/firewall EXTIF eth0 (203.0.113.1) TUNIF tun1 (192.168.1.2) INTIF eth1 (10.0.2.1, 172.16.2.1) SERVER-3 is a server on the LAN. Postfix listens/binds on 10.0.2.47 EXTIF eth0 (10.0.2.47, 172.16.2.47) Policy routing + (D)NAT makes sure that outbound mail flows from Postfix on SERVER-3, through the router on SERVER-2 and over the VPN , and out via SERVER-1. Likewise, inbound mail flows the opposite direction. I've read http://www.postfix.org/postconf.5.html#proxy_interfaces, and, my postfix config has inet_interfaces = 10.0.2.47 inet_protocols = ipv4 mydestination = $myhostname, localhost.$mydomain, localhost mynetworks = 10.0.2.0/24 172.16.2.0/24 127.0.0.0/8 proxy_interfaces = 198.51.100.1, 198.51.100.2 smtp_bind_address = 10.0.2.47 So, mail's sending/receiving okay. But I don't completely understand use "proxy_interfaces" even after re-reading a couple times. With the servers setup like above is the "proxy_interfaces" correct & enough? Mainly looking to prevent any loops/relays/etc that I haven't found in my testing so far. Just getting verification from someone more experienced would help out! Terry
