nginx.conf примерно вот так
##########################
user www-data;
worker_processes 4;
error_log /var/log/nginx/error.log warn;

events {
worker_connections 1024;
}

http {
include /etc/nginx/mime.types;
default_type application/octet-stream;
log_format main '$remote_addr - - [$time_local] "$request" $status $body_bytes_sent "$http_referer" "$http_user_agent"'
log_format combined '$remote_addr - - [$time_local] "$request" $status $body_bytes_sent "$http_referer" "$http_user_agent" "$http_host" $request_time "$http_x_forwarded_for" "$http_via" "$gzip_ratio"';
access_log /var/log/nginx/access.log combined;

access_log /var/log/nginx/access.log main;

sendfile on;

server {

listen IP:80;
charset off;
access_log /var/log/nginx/IP1.access.log main;
location / {
proxy_pass http://IP2:80/;
proxy_redirect off;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}
}

}
##################################
Ну а Apache
Listen IP2:80
(предпологаеться что Апач настроен без nginx проксирования)