Nginx服务器的HTTP代理服务

• 网络初始化之listen常见配置

   listen 127.0.0.1:8000;
   listen 127.0.0.1;
   listen 8000;
   listen *:8000;
   listen localhost:8000;
   listen [::]:8000;
   listen [fe80::1];
   listen unix:/var/run/nginx.sock;

• 配置实例一：对所有请求实现一般轮询规则的负载均衡

     http {
  
          upstream live_node {                        # 配置后端服务器组
              #max_fails默认值为1,fail_timeout默认值为10s,max_fails=0表示不做检查
              server 127.0.0.1:8089 weight=1 max_fails=1  fail_timeout=10s;   
              server 127.0.0.1:8088;
              keepalive 32;
              hash $request_uri consistent;
          }
  
          server {
              listen 80;
              server_name  localhost;
              location / {
                  proxy_pass http://live_node;         # 注意：proxy_pass后面的路径不带uri时，其会将location的uri传递给后端主机
                  proxy_set_header Host $host;         # 保留客户端的真实信息
                  proxy_set_header Host $host:$server_port;
                  proxy_set_header X-Real-IP $remote_addr;
                  proxy_set_header X-Real-PORT $remote_port;
                  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
                  
                  proxy_redirect off;
                  proxy_buffer_size  128k;
                  proxy_buffers   32 32k;
                  proxy_busy_buffers_size 128k;
              }
          }
  
          server {                    # 配置虚拟服务器8088
              listen 8088;
              server_name  localhost;
              location / {
                  root   /usr/local/nginx/html2;      
                  index  index.html index.htm;
              }
          }
  
          server {                    # 配置虚拟服务器8089
              listen 8089;
              server_name  localhost;
              location / {
                  root   /usr/local/nginx/html3;
                  index  index.html index.htm;
              }
          }
      }
  • Nginx-proxy 详解文章链接
    • 查看错误日志 upstream sent too big header while reading response header from upstream
    • Nginx-proxy_buffer_size and fastcgi_buffer
    • http://wiki.nginx.org/NginxHttpProxyModule
    • http://blog.sina.com.cn/s/blog_5dc960cd0100i4mt.html

  参数：keepalive connections;

  补充：由于短连接消耗前端代理服务器的资源现象严重,因此会将一部分连接定义为长连接以节省资源
  FUN：#为每个worker进程保留的空闲的长连接数量
  FUN：#定义nginx与后端服务器的保持连接的数量

  参数：hash $request_uri consistent;

  FUN：#[consistent]; 使用一致性哈希算法, 建议开启此项
  FUN：#基于指定的key的hash表来实现对请求的调度，此处的key可以直接文本、变量或二者的组合；
  FUN：#将请求分类，同一类请求将发往同一个upstream server；

• 配置实例二：对所有请求实现加权轮询规则负载均衡

     http {
  
          upstream live_node {                        # 配置后端服务器组
              server 127.0.0.1:8089 weight=5;         # 这个处理客户端请求会多些 
              server 127.0.0.1:8088 weight=1;         # 默认 weight = 1
          }
  
          server {
              listen 80;
              server_name  localhost;
              location / {
                  #proxy_pass http://new_uri/;         # 注意：proxy_pass后面的路径是一个uri时，其会将location的uri替换为proxy_pass的uri
                  proxy_pass http://live_node;         
                  proxy_set_header Host $host;         # 保留客户端的真实信息
              }
          }
  
          server {                    # 配置虚拟服务器8088
              listen 8088;
              server_name  localhost;
              location / {
                  root   /usr/local/nginx/html2;      
                  index  index.html index.htm;
              }
          }
  
          server {                    # 配置虚拟服务器8089
              listen 8089;
              server_name  localhost;
              location / {
                  root   /usr/local/nginx/html3;
                  index  index.html index.htm;
              }
          }
      }

• 配置实例三：对特定资源实现负载均衡

     http {
  
          upstream videobackend {                     # 配置后端服务器组视频代理
              server 127.0.0.1:8088;         
              server 127.0.0.1:8089;        
          }
  
          upstream filebackend {                      # 配置后端服务器组文件代理
              server 127.0.0.1:8888;        
              server 127.0.0.1:8889;        
          }
  
          server {
              listen 80;
              server_name  localhost;
              location /video/ {
                  proxy_pass http://videobackend;      # 视频代理
                  proxy_set_header Host $host;
                  proxy_set_header X-Real-IP $remote_addr;        #  proxy_set_header field value; 设定发往后端主机的请求报文的请求首部的值
                  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;         
              }
  
              location /file/ {
                  proxy_pass http://filebackend;       # 文件代理
                  proxy_set_header Host $host;
                  proxy_set_header X-Real-IP $remote_addr;
                  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;         
              }
          }
  
          server {                    # 配置虚拟服务器8088
              listen 8088;
              server_name  localhost;
              location /video {
                   alias   /usr/local/nginx/html2;
              }
          }
  
          server {                    # 配置虚拟服务器8089
              listen 8089;
              server_name  localhost;
              location /video {
                   alias   /usr/local/nginx/html3;
              }
          }
  
          server {                    # 文件虚拟服务器1
              listen 8888;
              server_name  localhost;
              location /file {
                  alias   /usr/local/nginx/html4;
              }
          }
  
          server {                    # 文件虚拟服务器2
              listen 8889;
              server_name  localhost;
              location /file {
                  alias   /usr/local/nginx/html5;
              }
          }
      }

  访问方式：http://127.0.0.1/video/demo.txt

  输出：this is video HTML2 demo2 8088
  输出：this is video HTML3 demo3 8089

  访问方式：http://127.0.0.1/file/demo.txt

  输出：this is file HTML4 demo4 8888
  输出：this is file HTML4 demo5 8889

  测数文件：demo.txt

  echo "this is video HTML2 demo2 8088" > ./html2/demo.txt

• 配置实例四：不同的域名实现负载均衡

     http {
  
          upstream frontend {                     # 配置后端服务器组视频代理
              server 127.0.0.1:8088;         
              server 127.0.0.1:8089;        
          }
  
          upstream backend {                      # 配置后端服务器组文件代理
              server 127.0.0.1:8888;        
              server 127.0.0.1:8889;        
          }
  
          server {
              listen 80;
              server_name  www.frontend.com;
              location /video/ {
                  proxy_pass http://frontend;      # 前台域名代理
                  proxy_set_header Host $host;
                  proxy_set_header X-Real-IP $remote_addr;
                  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;         
              }
          }
  
          server {
              listen 8088;
              server_name  www.backend.com;
              location /video/ {
                  proxy_pass http://backend;      # 后台域名代理
                  proxy_set_header Host $host;
                  proxy_set_header X-Real-IP $remote_addr;
                  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;         
              }
          }
  
      }

• 配置实例五：实现带有URL重写的负载均衡

     http {
  
          upstream backend {                      # 配置后端服务器组
              server 127.0.0.1:8888;        
              server 127.0.0.1:8889;        
          }
  
          server {
              listen 80;
              server_name  www.backend.com;
              index  index.html index.htm;
              location /file/ {
                  rewrite ^(/file/.*)/media/(.*)\.*$ $1/mp3/$2.mp3 last;        
              }
  
              location / {
                  proxy_pass http://frontend;      # 前台域名代理
                  proxy_set_header Host $host;      
              }
          }
  
      }

  客户端请求URL为：http://www.backend.com/file/download/media/1.mp3
  [1]：虚拟主机location /file/块将该URL进行重写为:http://www.backend.com/file/download/media/mp3/1.mp3
  [2]：新的URL再有 location /块转发转发到后端的backend服务器组中实现负载均衡
  [3]: 这样就可以实现URL重写的负载均衡