Nginx基于TCP的负载均衡的配置例子

原文：https://blog.csdn.net/bigtree_3721/article/details/72833955

nginx-1.9.0 已发布，该版本增加了 stream 模块用于一般的 TCP 代理和负载均衡。

The ngx_stream_core_module module is available since version 1.9.0. This module is not built by default, it should be enabled with the --with-stream configuration parameter.

ngx_stream_core_module 这个模块在1.90版本后将被启用。但是并不会默认安装，需要在编译时通过指定 --with-stream 参数来激活这个模块。 
其他改进包括： 
Change: 删除过时的 aio 和 rtsig 事件处理方法 
Feature: 可在 upstream 块中使用 "zone" 指令 
Feature: 流模块，支持 TCP 代理和负载均衡 
Feature: ngx_http_memcached_module 支持字节范围 
Feature: Windows 版本支持使用共享内存，带随机化地址空间布局. 
Feature: "error_log" 指令可在 mail 和 server 级别 
Bugfix: the "proxy_protocol" parameter of the "listen" directive did not work if not specified in the first "listen" directive for a listen socket.

编译安装：略
最后贴一下官方分享的stream模块的简单配置demo：
http://nginx.org/en/docs/stream/ngx_stream_core_module.html

worker_processes auto;

error_log /var/log/nginx/error.log info; 
events { 
    worker_connections 1024; 
}

stream { 
    upstream backend { 
        hash $remote_addr consistent; 
        server backend1.example.com:12345 weight=5; 
        server 127.0.0.1:12345 max_fails=3 fail_timeout=30s; 
        server unix:/tmp/backend3; 
    }

server { 
        listen 12345; 
        proxy_connect_timeout 1s; 
        proxy_timeout 3s; 
        proxy_pass backend; 
    }

server { 
        listen [::1]:12345; 
        proxy_pass unix:/tmp/stream.socket; 
    } 
}

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在此我做了一个tcp反向解析的小实验

背景：125.208.14.177:3306    数据库1 
      125.208.14.177:3306    数据库2 
      218.78.186.162        nginx服务器

配置文件

worker_processes auto;

error_log /var/log/nginx/error.log info; 
events { 
    worker_connections 1024; 
}

stream { 
    upstream backend { 
        hash $remote_addr consistent; 
        server 125.208.14.177:3306 weight=5 max_fails=3 fail_timeout=30s; 
        server 125.208.14.177:3307 weight=4 max_fails=3 fail_timeout=30s; 
    }

server { 
        listen 12345; 
        proxy_connect_timeout 1s; 
        proxy_timeout 3s; 
        proxy_pass backend; 
    }

}

测试：

[root@iZ236mlq2naZ ~]# mysql -uroot -p'******' -P12345 -h218.78.186.162 -e "select * from test" test

Warning: Using a password on the command line interface can be insecure.
+-----------------------------+
| t                          |
+-----------------------------+
| this is 125.208.14.177:3306 |
+-----------------------------+
[root@iZ236mlq2naZ ~]# mysql -uroot -p'*****' -P12345 -h218.78.186.162 -e "select * from test" test
Warning: Using a password on the command line interface can be insecure.
^[[A+-----------------------------+
| t                          |
+-----------------------------+
| this is 125.208.14.177:3307 |
+-----------------------------+
[root@iZ236mlq2naZ ~]# mysql -uroot -p'*****' -P12345 -h218.78.186.162 -e "select * from test" test
Warning: Using a password on the command line interface can be insecure.
+-----------------------------+
| t                          |
+-----------------------------+
| this is 125.208.14.177:3306 |
+-----------------------------+
[root@iZ236mlq2naZ ~]# mysql -uroot -p'******' -P12345 -h218.78.186.162 -e "select * from test" test
Warning: Using a password on the command line interface can be insecure.
+-----------------------------+
| t                          |
+-----------------------------+
| this is 125.208.14.177:3306 |
+-----------------------------+

再做一个读写分离的实验：
配置文件

worker_processes auto;

error_log /var/log/nginx/error.log info; 
events { 
    worker_connections 1024; 
}

stream { 
    upstream readdb { 
        hash $remote_addr consistent;                                    ---作为read库 
        server 125.208.14.177:3306 weight=5 max_fails=3 fail_timeout=30s; 
        server 125.208.14.177:3307 weight=4 max_fails=3 fail_timeout=30s; 
    }

server { 
        listen 12345; 
        proxy_connect_timeout 1s; 
        proxy_timeout 3s; 
        proxy_pass readdb; 
    }

upstream writedb{ 
      hash $remote_addr consistent; 
      server 125.208.14.177:3308 max_fails=3 fail_timeout=30s;      ---作为write库 
    } 
    server { 
        listen 23456; 
        proxy_connect_timeout 1s; 
        proxy_timeout 3s; 
        proxy_pass writedb; 
    } 
 
}

注意下：绿色stream就是表示该nginx使用了tcp来负载均衡，而以前的是基于http的负载均衡。http负载均衡在配置文件中在绿色stream地方要用http来替换，见本博的另外一篇关于nginx http负载均衡的例子。

最后可以将http负载与tcp负载写一起达到多重目的。