说明：
nginx处理静态内容是把好手，apache虽然占用内存多了点，性能上稍逊，但一直比较稳健。倒是nginx的FastCGI有时候会出现502 Bad Gateway错误。一个可选的方法是nginx做前端代理，处理静态内容，动态请求统统转发给后端apache。
本文就是实现Nginx作为前端，apache作为后端。当用户访问的是80端口的nginx，然后nginx将静态内容留给自己，其余的转发给非80端口的apache，apache处理完毕后再回传给nginx。例如这里我分别访问www.test.com/a.html,www.test.com/info.php。nginx因为做前面，nginx的访问日志应该都有a.html,info.php的记录；而apache作为后端，只处理php请求，应该只有info.php的访问记录。
实现：
1.修改nginx配置文件，将php动态请求转发给apache
# cat /usr/local/nginx/conf/vhosts/test.conf
server
{
listen 80;
server_name www.test.com test.com;
index index.html index.htm index.php default.html default.htm default.php;
root /home/www/data/test;
access_log /usr/local/nginx/logs/test-access.log;
# nginx找不到文件时，转发请求给后端Apache
error_page 404 @proxy;
# 这是原来lnmp时，nginx自己将php请求提交到127.0.0.1:9000。现在由apache来处理，因此注释掉这段。
#location ~ .*.(php|php5)?$
#{
# fastcgi_pass 127.0.0.1:9000;
# fastcgi_index index.php;
# include fastcgi.conf;
#}
location ~ .*.(gif|jpg|jpeg|png|bmp|swf)$
{
expires 30d;
}
location ~ .*.(js|css)?$
{
expires 12h;
}
# 动态文件.php请求转发给后端Apache
location ~ .php$ {
# 向后端服务器发起请求时添加指定的header头信息
proxy_set_header Host $http_host;
# 向后端服务器发送真实 IP
proxy_set_header X-Real-IP $remote_addr;
# 让后端如php能直接通过变量获取真实IP
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_pass http://127.0.0.1:8080;
}
# nginx找不到文件时，转发请求给后端Apache
location @proxy {
proxy_set_header Host $http_host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_pass http://127.0.0.1:8080;
}
}
然后只要开启nginx监听80端口，apache监听8080端口，开启php，就可以了。这边，我同时开启nginx，apache的访问日志。当我访问www.test.com/a.html,www.test.com/info.php时，nginx记录下了所有a.html,info.html的访问请求。
nginx访问日志
192.168.45.30 - - [19/Jun/2013:14:41:06 +0800] "GET /a.html HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.110 Safari/537.36" 192.168.45.30 - - [19/Jun/2013:14:41:06 +0800] "GET /favicon.ico HTTP/1.1" 404 209 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.110 Safari/537.36" 192.168.45.30 - - [19/Jun/2013:14:41:08 +0800] "GET /info.php HTTP/1.1" 200 10518 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.110 Safari/537.36" 192.168.45.30 - - [19/Jun/2013:14:41:08 +0800] "GET /info.php?=PHPE9568F35-D428-11d2-A769-00AA001ACF42 HTTP/1.1" 200 2158 "http://www.test.com/info.php" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.110 Safari/537.36" 192.168.45.30 - - [19/Jun/2013:14:41:08 +0800] "GET /info.php?=PHPE9568F34-D428-11d2-A769-00AA001ACF42 HTTP/1.1" 200 2536 "http://www.test.com/info.php" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.110 Safari/537.36" 192.168.45.30 - - [19/Jun/2013:14:41:08 +0800] "GET /favicon.ico HTTP/1.1" 404 209 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.110 Safari/537.36" 192.168.45.30 - - [19/Jun/2013:14:41:09 +0800] "GET /info.php HTTP/1.1" 200 10518 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.110 Safari/537.36"
当我访问www.test.com/a.html,www.test.com/info.php时，apache只记录了info.html的访问请求。说明nginx将php请求转发给了apache。这里可以看到来源都是127.0.0.1。而不是真实的来源ip。
apache访问日志
127.0.0.1 - - [19/Jun/2013:11:04:16 +0800] "GET /favicon.ico HTTP/1.0" 404 209 127.0.0.1 - - [19/Jun/2013:11:04:23 +0800] "GET /favicon.ico HTTP/1.0" 404 209 127.0.0.1 - - [19/Jun/2013:11:04:31 +0800] "GET /favicon.ico HTTP/1.0" 404 209 127.0.0.1 - - [19/Jun/2013:11:04:34 +0800] "GET /favicon.ico HTTP/1.0" 404 209 127.0.0.1 - - [19/Jun/2013:11:04:39 +0800] "GET /favicon.ico HTTP/1.0" 404 209 127.0.0.1 - - [19/Jun/2013:11:05:09 +0800] "GET /favicon.ico HTTP/1.0" 404 209 127.0.0.1 - - [19/Jun/2013:11:05:18 +0800] "GET /favicon.ico HTTP/1.0" 404 209 127.0.0.1 - - [19/Jun/2013:11:05:24 +0800] "GET /info.php HTTP/1.0" 200 55447 127.0.0.1 - - [19/Jun/2013:11:05:24 +0800] "GET /info.php?=PHPE9568F34-D428-11d2-A769-00AA001ACF42 HTTP/1.0" 200 2524 127.0.0.1 - - [19/Jun/2013:11:05:24 +0800] "GET /info.php?=PHPE9568F35-D428-11d2-A769-00AA001ACF42 HTTP/1.0" 200 2146 127.0.0.1 - - [19/Jun/2013:11:05:24 +0800] "GET /favicon.ico HTTP/1.0" 404 209
2.apache添加mod_rpaf， 获取nginx转发过来的真实IP
mod_rpaf模块不是必须安装，除非你需要开启apache日志，但有多此一举之嫌，因为已经有nginx日志了，再开apache日志话就出现重复了。
Apache rpaf模块作用是获取Nginx转发过来的真实IP，否则在Apache日子中来访IP全部为127.0.0.1。
# wget http://stderr.net/apache/rpaf/download/mod_rpaf-0.6.tar.gz # tar zxvf mod_rpaf-0.6.tar.gz # cd mod_rpaf-0.6 # /usr/local/www/apache/bin/apxs -i -c -n mod_rpaf-2.0.so mod_rpaf-2.0.c
安装过程中，若出现error: ‘conn_rec’ has no member named ‘remote_ip，请参考附录1.mod_rpaf-2.0.c error: ‘conn_rec’ has no member named ‘remote_ip
# vim /usr/local/apache/conf/httpd.conf //在LoadModule后添加以下内容 LoadModule rpaf_module modules/mod_rpaf-2.0.so RPAFenable On RPAFproxy_ips 127.0.0.1 RPAFsethostname On RPAFheader X-Forwarded-For
下面是apache添加了mod_rpaf模块后，apache的访问日志
192.168.45.30 - - [19/Jun/2013:14:41:09 +0800] "GET /info.php?=PHPE9568F35-D428-11d2-A769-00AA001ACF42 HTTP/1.1" 200 2158 "http://www.test.com/info.php" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.110 Safari/537.36" 192.168.45.30 - - [19/Jun/2013:14:41:09 +0800] "GET /info.php?=PHPE9568F34-D428-11d2-A769-00AA001ACF42 HTTP/1.1" 200 2536 "http://www.test.com/info.php" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.110 Safari/537.36" 192.168.45.30 - - [19/Jun/2013:14:41:09 +0800] "GET /favicon.ico HTTP/1.1" 404 209 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.110 Safari/537.36" 192.168.45.30 - - [19/Jun/2013:14:41:09 +0800] "GET /info.php HTTP/1.1" 200 10520 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.110 Safari/537.36" 192.168.45.30 - - [19/Jun/2013:14:41:09 +0800] "GET /info.php?=PHPE9568F34-D428-11d2-A769-00AA001ACF42 HTTP/1.1" 200 2536 "http://www.test.com/info.php" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.110 Safari/537.36"
附录：
附录1.mod_rpaf-2.0.c error: ‘conn_rec’ has no member named ‘remote_ip
mod_rpaf-2.0.c: In function ‘rpaf_cleanup’:
mod_rpaf-2.0.c:150: error: ‘conn_rec’ has no member named ‘remote_ip’
mod_rpaf-2.0.c:151: error: ‘conn_rec’ has no member named ‘remote_addr’
mod_rpaf-2.0.c:151: warning: implicit declaration of function ‘inet_addr’
mod_rpaf-2.0.c:151: error: ‘conn_rec’ has no member named ‘remote_ip’
mod_rpaf-2.0.c: In function ‘change_remote_ip’:
mod_rpaf-2.0.c:164: error: ‘conn_rec’ has no member named ‘remote_ip’
mod_rpaf-2.0.c:183: error: ‘conn_rec’ has no member named ‘remote_ip’
mod_rpaf-2.0.c:186: error: ‘conn_rec’ has no member named ‘remote_ip’
mod_rpaf-2.0.c:187: error: ‘conn_rec’ has no member named ‘remote_addr’
mod_rpaf-2.0.c:187: error: ‘conn_rec’ has no member named ‘remote_ip’
apxs:Error: Command failed with rc=65536
只要将mod_rpaf-2.0.c的150、151、164、183、186、187这几行的remote_ip修改成client_ip，remote_addr修改成client_addr，
然后再/usr/local/www/apache/bin/apxs -i -c -n mod_rpaf-2.0.so mod_rpaf-2.0.c即可