基于CentOS 7配置Nginx反向代理

Nginx作为反向代理服务器被广泛使用在各大互联网企业。它简单易用，可以根据业务的需求将其不同的业务类型代理至不同的服务器，将整个站点请求压力按类型分摊到不同的服务器。该方式使的整个站点请求性能得以极大的提升。本文简要描述了Nginx几种不同情形的代理演示，供大家参考。

一、反向代理及演示环境描述

1、反向代理

在计算机网络中，反向代理是一种代理服务器，代表客户端从一个或多个服务器检索资源。然后将这些资源返回给客户机，就像它们源自Web服务器本身一样。与正向代理相反，正向代理是与其关联的客户端联系任何服务器的中介，反向代理是任何客户端与其关联的服务器进行联系的中介。

有关正向代理可参考：基于CentOS 7配置Nginx正向代理

2、本演示中的几个服务器

二、常规反向代理配置

1、后端服务器配置(Apache)

后端Apache服务器主机名及IP  # hostname  centos7-web.example.com  # more /etc/redhat-release  CentOS Linux release 7.2.1511 (Core)  # ip addr|grep inet|grep global  inet 172.24.8.128/24 brd 172.24.8.255 scope global eno16777728  # systemctl start httpd.service  # echo "This is a httpd test page.">/var/www/html/index.html  # curl http://localhost  This is a httpd test page.

2、前端Nginx反向代理服务器配置

前端Nginx服务器主机名及IP  # hostname  centos7-router  # more /etc/redhat-release  CentOS Linux release 7.2.1511 (Core)  # ip addr |grep inet|grep global  inet 172.24.8.254/24 brd 172.24.8.255 scope global eno16777728  inet 192.168.1.175/24 brd 192.168.1.255 scope global dynamic eno33554960Nginx版本  # nginx -V  nginx version: nginx/1.10.2添加一个新的配置文件用作反向代理  # vim /etc/nginx/conf.d/reverse_proxy.conf  server {    listen 8090;    server_name localhost;  location / {    proxy_pass http://172.24.8.128; ###反向代理核心指令    proxy_buffers 256 4k;    proxy_max_temp_file_size 0;    proxy_connect_timeout 30;    proxy_cache_valid 200 302 10m;    proxy_cache_valid 301 1h;    proxy_cache_valid any 1m;    }  }# systemctl reload nginx# ss -nltp|grep nginx|grep 8090LISTEN 0 128 *:8090 *:* users:(("nginx",pid=78023,fd=8),("nginx",pid=78021,fd=8))# curl http://localhost:8090 ##基于本地测试This is a httpd test page.查看Apache服务器日志# more /var/log/httpd/access_log ##请求IP地址为172.24.8.254，当从其他机器请求时也是172.24.8.254这个IP172.24.8.254 - - [30/Oct/2017:14:02:38 +0800] "GET / HTTP/1.0" 200 27 "-" "curl/7.29.0"

3、反向代理服务器及后端服务器日志格式设置

为Nginx服务器添加proxy_set_header指令，修改后如下  # grep proxy_set_header -B2 /etc/nginx/conf.d/reverse_proxy.conf  location / {    proxy_pass http://172.24.8.128;    proxy_set_header X-Real-IP $remote_addr;    }  # systemctl reload nginx.service后端服务器Apache日志格式设置  # vim /etc/http/conf/httpd.conf    # LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\"" combined #注释此行，添加下一行    LogFormat "%{X-Real-IP}i %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\"" combined #关键描述 {X-Real-IP}i  # ip addr|grep inet|grep global    #从1.132主机访问  inet 192.168.1.244/24 brd 192.168.1.255 scope global eth0  # curl http://192.168.1.175:8090  #从1.244主机访问  This is a httpd test page#再次查看apache访问日志，如下，不再是代理服务器IP地址，此时显示为1.244  192.168.1.244 - - [30/Oct/2017:15:49:07 +0800] "GET / HTTP/1.0" 200 27 "-" "curl/7.19.7 (x86_64-redhat-linux-gnu)  libcurl/7.19.7 NSS/3.14.0.0 zlib/1.2.3 libidn/1.18 libssh2/1.4.2"

二、基于目录匹配反向代理

后端服务器采用Nginx的配置  # more /etc/redhat-release ##os平台及ip地址  CentOS release 6.7 (Final)  # ip addr|grep eth0|grep global  inet 192.168.1.132/24 brd 192.168.1.255 scope global eth0  # nginx -v ##nginx版本  nginx version: nginx/1.10.2  # mkdir -pv /usr/share/nginx/html/images ##创建图片目录  mkdir: created directory `/usr/share/nginx/html/images'  # cp /usr/share/backgrounds/nature/*.jpg /usr/share/nginx/html/images/. ##复制图片文件  # cp /etc/nginx/conf.d/default.conf /etc/nginx/conf.d/default.conf.bk  # vim /etc/nginx/conf.d/default.conf ##此处直接修改缺省配置文件  server {  listen 80 default_server;  listen [::]:80 default_server;  server_name _;  root /usr/share/nginx/html;  # Load configuration files for the default server block.  include /etc/nginx/default.d/*.conf;  location / {    }  location /images {    alias /usr/share/nginx/html/images; ##此处配置了别名    }  error_page 404 /404.html;  location = /40x.html {    }  error_page 500 502 503 504 /50x.html;  location = /50x.html {    }  }# /etc/init.d/nginx reloadReloading nginx: [ OK ]前端Nginx配置  # vim /etc/nginx/conf.d/reverse_proxy.conf  server {  listen 8090;  server_name localhost;  location / {    proxy_pass http://172.24.8.128;    proxy_set_header X-Real-IP $remote_addr;    }  location /images { ##将images目录下的文件代理至192.168.1.132    proxy_pass http://192.168.1.132;    proxy_set_header X-Real-IP $remote_addr;    }  }# systemctl reload nginx验证代理情况在ip为192.168.1.244测试对images目录下的jpg文件请求(基于浏览器查看jpg成功，此处省略贴图)  # ip addr|grep inet|grep global  inet 192.168.1.244/24 brd 192.168.1.255 scope global eth0  # curl -I http://192.168.1.175:8090/images/Garden.jpg  HTTP/1.1 200 OK  Server: nginx/1.12.2  Date: Tue, 31 Oct 2017 01:48:18 GMT  Content-Type: image/jpeg  Content-Length: 264831  Connection: keep-alive  Last-Modified: Mon, 30 Oct 2017 08:21:28 GMT  ETag: "59f6e108-40a7f"  Accept-Ranges: bytes

三、基于特定文件类型的反向代理配置

php服务器端配置(ip 192.168.1.132)  # ss -nltp|grep php  LISTEN 0 128 192.168.1.132:9000 *:* users:(("php-fpm",7147,8),("php-fpm",7148,0),("php-fpm",7149,0))  # mkdir -pv /data ###存放php代码  # echo "/data 192.168.1.0/24(rw)" >/etc/exports  # /etc/init.d/rpcbind start  # /etc/init.d/nfslock start  # /etc/init.d/nfs start  # echo "<?php phpinfo();?>" > /data/index.phpNginx代理端配置(ip 192.168.1.175)  # mkdir /data  # mount -t nfs 192.168.1.132:/data /data  # ls /data  index.php  # vim /etc/nginx/conf.d/reverse_proxy.conf  server {  listen 8090;  server_name localhost;  location / {    proxy_pass http://172.24.8.128;    proxy_set_header X-Real-IP $remote_addr;    }  location /images {    proxy_pass http://192.168.1.132;    proxy_set_header X-Real-IP $remote_addr;    }  location ~ \.php$ {    root /data;    fastcgi_pass 192.168.1.132:9000;    fastcgi_index index.php;    fastcgi_param SCRIPT_FILENAME /scripts$fastcgi_script_name;    include fastcgi_params;    }  }# systemctl restart nginx测试反向代理至php  [root@ydq05 ~]# ip addr|grep inet|grep global  inet 192.168.1.244/24 brd 192.168.1.255 scope global eth0  [root@ydq05 ~]# curl -I http://192.168.1.175:8090/index.php  HTTP/1.1 200 OK  Server: nginx/1.12.2  Date: Tue, 31 Oct 2017 03:22:59 GMT  Content-Type: text/html; charset=UTF-8  Connection: keep-alive  X-Powered-By: PHP/5.6.0

四、基于upstream 配置反向代理至tomcat

Nginx upstream指令也可以将请求代理到后端服务器
如下示例，结合upstream指令演示将其代理到tomcat

# vim /etc/nginx/conf.d/tomcat.conf upstream app {                server localhost:8080;                keepalive 32;}server {    listen 80;    server_name localhost;    location / {        proxy_set_header Host $host;        proxy_set_header x-for $remote_addr;        proxy_set_header x-server $host;        proxy_set_header x-agent $http_user_agent;        proxy_pass http://app;    }}[root@node132 conf.d]# ss -nltp|grep javaLISTEN    0  1    ::ffff:127.0.0.1:8005  :::*      users:(("java",39559,45))LISTEN    0  100                :::8009  :::*      users:(("java",39559,43))LISTEN    0  100                :::8080  :::*      users:(("java",39559,42))tomcat版本[root@node132 conf.d]# /usr/local/tomcat/bin/catalina.sh versionUsing CATALINA_BASE:  /usr/local/tomcatUsing CATALINA_HOME:  /usr/local/tomcat            ....Server version: Apache Tomcat/7.0.69Server built:  Apr 11 2016 07:57:09 UTCServer number:  7.0.69.0OS Name:        LinuxOS Version:    2.6.32-573.el6.x86_64Architecture:  amd64JVM Version:    1.7.0_79-b15JVM Vendor:    Oracle Corporation验证结果# curl http://localhost<!DOCTYPE html><html lang="en">    <head>        <title>Apache Tomcat/7.0.69</title>        <link href="favicon.ico" rel="icon" type="image/x-icon" />        <link href="favicon.ico" rel="shortcut icon" type="image/x-icon" />        <link href="tomcat.css" rel="stylesheet" type="text/css" />    </head>    ......

五、proxy模块指令描述

proxy模块的可用配置指令非常多，它们分别用于定义proxy模块工作时的诸多属性，如连接超时时长、代理时使用http协议版本等。下面对常用的指令做一个简单说明。

proxy_connect_timeout
  nginx将一个请求发送至upstream server之前等待的最大时长；
proxy_cookie_domain
  将upstream server通过Set-Cookie首部设定的domain属性修改为指定的值，其值可以为一个字符串、正则表达式的模式或一个引用的变量；
proxy_cookie_path
   将upstream server通过Set-Cookie首部设定的path属性修改为指定的值，其值可以为一个字符串、正则表达式的模式或一个引用的变量；
proxy_hide_header
  设定发送给客户端的报文中需要隐藏的首部；
proxy_pass
  指定将请求代理至upstream server的URL路径；
proxy_set_header
  将发送至upsream server的报文的某首部进行重写；
proxy_redirect
  重写location并刷新从upstream server收到的报文的首部；
proxy_send_timeout
  在连接断开之前两次发送至upstream server的写操作的最大间隔时长；
proxy_read_timeout
   在连接断开之前两次从接收upstream server接收读操作的最大间隔时长；

如下面的一个示例：    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;    client_max_body_size 10m;    client_body_buffer_size 128k;    proxy_connect_timeout 30;    proxy_send_timeout 15;    proxy_read_timeout 15;

注：最后更新时间20171110，添加反向代理至tomcat内容