I reconfigured one of my VPS to use the proxy protocol instead of NAT to forward external traffic to my postfix (postscreen). I have set up nginx to forward the TCP stream to port 10025 using proxy_protocol v1 (afaik v2 is not yet supported by nginx), and when connecting I am getting back the response “421 4.3.2 No system resources” and the log message
haproxy/postscreen[903]: warning: haproxy read: unsupported protocol type: PROXY TCP6 2a00:f48:1003:3489::1 2a03:4000:6:1487:83b:12ff:fe79:c546 52700 25\r\n. I changed nginx to accept ipv4 only and succeeded. Then in https://github.com/vdukhovni/postfix/blob/7240584ca17cdc3ea313bb72180ee265f01eb2b1/postfix/src/global/haproxy_srvr.c it looks like tcp6 support is compiled conditionally. Is there a good reason for that? My understanding is, that the proxied protocol is entirely independent of the protocols available locally. Thanks, Joachim
