My http/https configuration using centos and nginx from the EPEL repo is as follows:
/etc/nginx/nginx.conf
user nginx;
worker_processes 1;
error_log /var/log/nginx/error.log;
pid /var/run/nginx.pid;
events {
worker_connections 1024;
}
http {
include /etc/nginx/mime.types;
default_type application/octet-stream;
log_format main '$remote_addr - $remote_user [$time_local] "$request" '
'$status $body_bytes_sent "$http_referer" '
'"$http_user_agent" "$http_x_forwarded_for"';
access_log /var/log/nginx/access.log main;
sendfile on;
tcp_nopush on;
keepalive_timeout 65;
gzip on;
server {
listen 80;
server_name rproxy.yourdomain.co.uk;
## use when niginx listens on a nonstandard port - the port in the rewrite
## rule needs to be the port nginx is actually listening on.
#rewrite ^(.*) https://rproxy.yourdomain.co.uk:80$1 permanent;
access_log /var/www/rproxy.yourdomain.co.uk/log/nginx.access.log;
error_log /var/www/rproxy.yourdomain.co.uk/log/nginx_error.log debug;
location / {
proxy_pass http://192.168.xx.x:81;
proxy_redirect default;
}
error_page 404 /404.html;
location = /404.html {
root /usr/share/nginx/html;
}
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root /usr/share/nginx/html;
}
}
server {
listen 443;
server_name rproxy.yourdomain.co.uk;
## use when niginx listens on a nonstandard port - the port in the rewrite
## rule needs to be the port nginx is actually listening on.
#rewrite ^(.*) https://rproxy.yourdomain.co.uk:443$1 permanent;
ssl on;
ssl_certificate /etc/pki/tls/certs/ca.crt;
ssl_certificate_key /etc/pki/tls/private/ca.key;
ssl_session_timeout 5m;
ssl_protocols SSLv2 SSLv3 TLSv1;
ssl_ciphers ALL:!ADH:!EXPORT56:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv2:+EXP;
ssl_prefer_server_ciphers on;
access_log /var/www/rproxy.yourdomain.co.uk/log/nginx.access.log;
error_log /var/www/rproxy.yourdomain.co.uk/log/nginx_error.log debug;
location / {
proxy_pass https://192.168.xx.x:444;
proxy_redirect default;
}
error_page 404 /404.html;
location = /404.html {
root /usr/share/nginx/html;
}
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root /usr/share/nginx/html;
}
}
include /etc/nginx/conf.d/*.conf;
}
/etc/nginx/conf.d/proxy.conf
## $proxy_port setting string is needed when
## nginx is listening on a nonstandard port
#proxy_set_header Host $host:$proxy_port;
#proxy_set_header X-Real-IP $remote_addr:$proxy_port;
#proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for:$proxy_port;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
client_max_body_size 10m;
client_body_buffer_size 128k;
client_header_buffer_size 64k;
proxy_connect_timeout 90;
proxy_send_timeout 90;
proxy_read_timeout 90;
proxy_buffer_size 16k;
proxy_buffers 32 16k;
proxy_busy_buffers_size 64k;
The link below gives the full details of my centos and nginx configuration:
http://www.zen212739.zen.co.uk/centos5-5/pub-centos-rproxy-nginx-install.txt
I only use one domain for webmail access, but adding another domain to this nginx config should not be too difficult.
Using nginx for an imap proxy is a little more difficult so set up. I am still looking into this myself.
Smtp traffic needs a store and forward mail server. A separate postfix setup would probably be a better option.
I set up a intel atom based centos xen server with a few vm's to essentially the same thing that you are attempting to do.