upstream backend {　　　   ip_hash;server 127.0.0.1:8080 weight=5 max_fails=2 fail_timeout=30s;server 127.0.0.1:800 weight=10 max_fails=2 fail_timeout=30s;}

        location / {proxy_pass http://backend;
            #root   html;#index  index.html index.htm;}

[root@cloud conf]# nginx -V
nginx version: nginx/1.9.9
built by gcc 4.4.7 20120313 (Red Hat 4.4.7-3) (GCC)
built with OpenSSL 1.0.1e-fips 11 Feb 2013
TLS SNI support enabled
configure arguments: --prefix=/usr/local/nginx --user=nginx --group=nginx --add-module=../ngx_cache_purge-2.3 \--with-http_ssl_module --with-http_stub_status_module --with-http_gzip_static_module --with-pcre --with-http_realip_module

user  nginx nginx;
worker_processes  2;error_log  logs/error.log;
#error_log  logs/error.log  notice;
#error_log  logs/error.log  info;pid        logs/nginx.pid;worker_rlimit_nofile 65535;events {use epoll;multi_accept on;worker_connections  4096;
}http {server_tokens  off;include       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  logs/access.log  main;open_log_file_cache max=2000 inactive=20s min_uses=2 valid=1m;proxy_set_header X-Real-IP $remote_addr;proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;limit_conn_zone $binary_remote_addr zone=addr:5m;limit_conn addr 100;sendfile        on;tcp_nopush     on;#keepalive_timeout  0;keepalive_timeout  65;client_header_timeout 2m;client_body_timeout 3m;reset_timedout_connection on;send_timeout 15s;client_max_body_size 10m;client_body_buffer_size 512k;open_file_cache max=65535 inactive=20s;open_file_cache_valid 30s;open_file_cache_errors on;open_file_cache_min_uses 2;gzip  on;gzip_disable "msie6";gzip_proxied any;gzip_comp_level 4;gzip_vary on;gzip_min_length 1k;gzip_types text/plain text/css application/json application/x-javascript text/xml application/xml application/xml+rss text/javasc
ript;proxy_connect_timeout 5;proxy_read_timeout 60;proxy_send_timeout 5;proxy_buffer_size 16k;proxy_buffers 4 64k;proxy_busy_buffers_size 128k;proxy_temp_file_write_size 128k;#注：proxy_temp_path和proxy_cache_path指定的路径必须在同一分区proxy_temp_path /cache/proxy_temp_dir;　　　　# 创建临时缓存目录#设置Web缓存区名称为cache_one，内存缓存空间大小为200MB，1天没有被访问的内容自动清除，硬盘缓存空间大小为30GB。proxy_cache_path /cache/proxy_cache_dir levels=1:2 keys_zone=cache_one:200m inactive=1d max_size=30g;   upstream backend {ip_hash;server 127.0.0.1:8080 weight=5  max_fails=2 fail_timeout=30;server 127.0.0.1:800 weight=10 max_fails=2 fail_timeout=30;}server {listen       80;server_name  localhost;#charset koi8-r;#access_log  logs/host.access.log  main;location / {#如果后端的服务器返回502、504、执行超时等错误，自动将请求转发到upstream负载均衡池中的另一台服务器，实现故障转移。　　　　 proxy_next_upstream http_502 http_504 error timeout invalid_header;　　proxy_pass http://backend;proxy_cache cache_one;proxy_cache_valid 200 304 12h;　　#对不同的HTTP状态码设置不同的缓存时间#以域名、URI、参数组合成Web缓存的Key值，Nginx根据Key值哈希，存储缓存内容到二级缓存目录内　　　　 proxy_cache_key $host$uri$is_args$args;expires 1d;#root   html;#index  index.html index.htm;}location ~ /purge(/.*) {proxy_cache_purge cache_one $host$1$is_args$args;}#error_page  404              /404.html;# redirect server error pages to the static page /50x.html#error_page   500 502 503 504  /50x.html;location = /50x.html {root   html;}# proxy the PHP scripts to Apache listening on 127.0.0.1:80##location ~ \.php$ {#    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;#}}# 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;#    }#}}