本文使用的Linux發(fā)行版：CentOS6.7 下載地址：https://wiki.centos.org/Download
一、安裝Nginx
下載源：wget http://nginx.org/packages/centos/6/noarch/RPMS/nginx-release-centos-6-0.el6.ngx.noarch.rpm
安裝源：yum install nginx-release-centos-6-0.el6.ngx.noarch.rpm
安裝Nginx：yum install nginx
啟動Nginx服務(wù)：service nginx start
停止Nginx服務(wù)：service nginx stop
查看Nginx運行狀態(tài)：service nginx status
檢查Nginx配置文件：nginx -t
服務(wù)運行中重新加載配置：nginx -s reload
添加Nginx服務(wù)自啟動：chkconfig nginx on
二、修改防火墻規(guī)則
修改Nginx所在主機的防火墻配置：vi /etc/sysconfig/iptables，將nginx使用的端口添加到允許列表中。
例如：-A INPUT -m state --state NEW -m tcp -p tcp --dport 80 -j ACCEPT （表示允許80端口通過）
修改Tomcat所在主機的防火墻配置：vi /etc/sysconfig/iptables，將tomcat使用的端口添加到允許列表中。
例如：-A INPUT -m state --state NEW -m tcp -p tcp --dport 8080 -j ACCEPT （表示允許8080端口通過）
如果主機上有多個tomcat的話，則按此規(guī)則添加多條，修改對應(yīng)的端口號即可。
保存后重啟防火墻：service iptables restart
三、Tomcat負載均衡配置
Nginx啟動時默認加載配置文件/etc/nginx/nginx.conf，而nginx.conf里會引用/etc/nginx/conf.d目錄里的所有.conf文件。
因此可以將自己定制的一些配置寫到單獨.conf文件里，只要文件放在/etc/nginx/conf.d這個目錄里即可，方便維護。
創(chuàng)建tomcats.conf：vi /etc/nginx/conf.d/tomcats.conf，內(nèi)容如下：

1. upstream tomcats

• {

•  ip_hash;
  

•  server 192.168.0.251:8080;
  

•  server 192.168.0.251:8081;
  

•  server 192.168.0.251:8082;
  

• }

注釋原有的配置

1. # location / {
2. # root /usr/share/nginx/html;
3. # index index.html index.htm;
4. #}

新增配置默認將請求轉(zhuǎn)發(fā)到tomcats.conf配置的upstream進行處理

location / {
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header REMOTE-HOST $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_pass http://tomcats; #與tomcats.conf里配置的upstream同名
}

保存后重新加載配置：nginx -s reload
四、靜態(tài)資源分離配置
修改default.conf：vi /etc/nginx/conf.d/default.conf，添加如下配置：

所有js,css相關(guān)的靜態(tài)資源文件的請求由Nginx處理

location ~.*.(js|css)$ {
root /opt/static-resources; #指定文件路徑
expires 12h; #過期時間為12小時
}

所有圖片等多媒體相關(guān)靜態(tài)資源文件的請求由Nginx處理

location ~.*.(html|jpg|jpeg|png|bmp|gif|ico|mp3|mid|wma|mp4|swf|flv|rar|zip|txt|doc|ppt|xls|pdf)$ {
root /opt/static-resources; #指定文件路徑
expires 7d; #過期時間為7天
}

五、修改SELinux安全規(guī)則
如果訪問Nginx時出現(xiàn)502 Bad Gateway錯誤，則可能是Nginx主機上的SELinux限制了其使用http訪問權(quán)限引起的，輸入命令setsebool -P httpd_can_network_connect 1 開啟權(quán)限即可。
文件/etc/nginx/nginx.conf完整配置如下：

user nginx;
worker_processes auto;

error_log /var/log/nginx/error.log warn;
pid /var/run/nginx.pid;
worker_rlimit_nofile 100000;

events {
use epoll;
multi_accept on;
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;
server_tokens off;
#tcp_nopush     on;

keepalive_timeout  65;

gzip on;
gzip_disable "msie6";
gzip_static on;
gzip_proxied any;
gzip_min_length 1000;
gzip_comp_level 4;
gzip_types text/plain text/css application/json application/x-javascript text/xml application/xml application/xml+rss text/javascript;

include /etc/nginx/conf.d/*.conf;

}

文件/etc/nginx/conf.d/default.conf完整配置如下：

server {
listen 80;
server_name localhost;

#charset koi8-r;
#access_log  /var/log/nginx/log/host.access.log  main;

#location / {
#    root   /usr/share/nginx/html;
#    index  index.html index.htm;
#}

location / {
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header REMOTE-HOST $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_pass http://web_servers;
}

location ~.*\.(js|css)$ {
    root    /opt/static-resources;
    expires     12h;
}

location ~.*\.(html|jpg|jpeg|png|bmp|gif|ico|mp3|mid|wma|mp4|swf|flv|rar|zip|txt|doc|ppt|xls|pdf)$ {
    root    /opt/static-resources;
    expires     7d;
}

#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   /usr/share/nginx/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;
#}

}