Nginx反向代理设置总结

负载均衡技术有很多种，常用的四/七层负载均衡技术包含很多，Nginx反向代理就是其中的一种方案。

以下的配置就是Nginx反向代理配置样例：

user  www www;
worker_processes  10;

error_log  /data1/logs/error.log crit;

pid        /usr/local/webserver/nginx/nginx.pid;

worker_rlimit_nofile 51200;

events {
	use epoll;
    worker_connections  51200;
}


http {
    include       mime.types;
    default_type  application/octet-stream;
	
	#charset utf-8
	
	server_names_hash_buckets_size 128;
	client_header_buffer_size 32k;
	large_client_header_buffers 4 32k;
	
    #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  logs/access.log  main;

    sendfile        on;
    #tcp_nopush     on;

    #keepalive_timeout  0;
    keepalive_timeout  65;
	
	tcp_nodelay on;
	
	fastcgi_connect_timeout 300;
	fastcgi_send_timeout 300;
	fastcgi_read_timeout 300;
	fastcgi_buffer_size 64k;
	fastcgi_buffers 4 64k;
	fastcgi_busy_buffers_size 128k;
	fastcgi_temp_file_write_size 128k;

    gzip on;
	gzip_min_length 1k;
	gzip_buffers 4 16k;
	gzip_http_version 1.1;
	gzip_comp_level 2;
	gzip_types text/plain application/javascript text/css application/xml;
	gzip_vary on;
	
	client_max_body_size 300m;
	client_body_buffer_size 128k;
	
	proxy_connect_timeout 600;
	proxy_read_timeout 600;
	proxy_send_timeout 600;
	proxy_buffer_size 16k;
	proxy_buffers 4 32k;
	proxy_busy_buffers_size 64k;
	proxy_temp_file_write_size 64k;
	
	upstream php_server_pool {
	  server 192.168.1.10:80 weight=4 max_fails=2 fail_timeout=30s;
	  server 192.168.1.11:80 weight=4 max_fails=2 fail_timeout=30s;
	  server 192.168.1.12:80 weight=4 max_fails=2 fail_timeout=30s;
	}
	
	upstream message_server_pool {
	  server 192.168.1.13:3245;
	  server 192.168.1.14:3245 down;
	}
	
	upstream php_server_pool {
	  server 192.168.1.15:80 weight=1 max_fails=2 fail_timeout=30s;
	  server 192.168.1.16:80 weight=1 max_fails=2 fail_timeout=30s;
	  server 192.168.1.17:80 weight=1 max_fails=2 fail_timeout=30s;
	  server 192.168.1.18:80 weight=1 max_fails=2 fail_timeout=30s;
	}
	
    server {
        listen       80;
        server_name  www.yourdomain.com;

        #charset koi8-r;

        access_log  /data1/logs/www.yourdomain.com_access.log;
		
		location / {
			proxy_next_upstream http_502 http_504 error timeout invalid_header;
			proxy_pass http://php_server_pool;
			proxy_set_header Host www.yourdomain.com;
			proxy_set_header X-Forwarded-For $remote_addr;
        }

        # proxy the PHP scripts to Apache listening on 127.0.0.1:80
        #
        #location ~ \.php$ {
        #    proxy_pass   http://127.0.0.1;
        #}

        # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
        #
        #location ~ \.php$ {
        #    root           html;
        #    fastcgi_pass   127.0.0.1:9000;
        #    fastcgi_index  index.php;
        #    fastcgi_param  SCRIPT_FILENAME  /scripts$fastcgi_script_name;
        #    include        fastcgi_params;
        #}

        # deny access to .htaccess files, if Apache's document root
        # concurs with nginx's one
        #
        #location ~ /\.ht {
        #    deny  all;
        #}
    }
	
	server {
		listen 80;
		server_name www1.yourdomain.com;
		
		localtion /message/ {
			proxy_pass http://message_server_pool;
			proxy_set_header Host $host;
		}
		
		localtion / {
			proxy_pass http://php_server_pool;
			proxy_set_header Host $host;
			proxy_set_header X-Forwarded-For $remote_addr;
		}
		
		access_log  /data1/logs/message.yourdomain.com_access.log;
	}

	server {
		listen 80;
		server_name bbs.yourdomain.com *.bbs.yourdomain.com;
		
		location / {
			proxy_pass http://bbs_server_pool;
			proxy_set_header Host $host;
			proxy_set_header X-Forwarded-For $remote_addr;
		}
		
		access_log off;
	}
	
    # another virtual host using mix of IP-, name-, and port-based configuration
    #
    #server {
    #    listen       8000;
    #    listen       somename:8080;
    #    server_name  somename  alias  another.alias;

    #    location / {
    #        root   html;
    #        index  index.html index.htm;
    #    }
    #}


    # HTTPS server
    #
    #server {
    #    listen       443 ssl;
    #    server_name  localhost;

    #    ssl_certificate      cert.pem;
    #    ssl_certificate_key  cert.key;

    #    ssl_session_cache    shared:SSL:1m;
    #    ssl_session_timeout  5m;

    #    ssl_ciphers  HIGH:!aNULL:!MD5;
    #    ssl_prefer_server_ciphers  on;

    #    location / {
    #        root   html;
    #        index  index.html index.htm;
    #    }
    #}

}

以上的配置中，upstream这个是用来配置一组可以在proxy_pass或者fastcgi_pass中使用的一组代理服务器，默认的负载均衡方式是轮询。server用来指定服务器的名称和参数，名称可以是一个域名、一个IP地址、端口号或者UNIX Socket。

proxy_pass和fastcgi_pass可以设置反向代理的upstream集群。

proxy_set_header用于向反向代理的服务器发送请求时增加指定的Header信息。使用Host参数是为了让后端服务器知道由哪个虚拟主机来处理，使用X-Forwarded-For是为了让后端服务器可以通过$_SERVER["HTTP_X_FORWARDED_FOR"]获取到用户的真实IP。