Nginx配置简单负载均衡

前提：因为本次需要两个软件在本机不同端口提供http服务，于是我准备一个tomcat在8080端口，另一个nodejs程序在3000端口，前者自不用提，后者可以到https://www.cnblogs.com/xiandedanteng/p/7514174.html 去下载并安装配置Node.js启动。

nginx主要通过proxy_pass来配置反向代理，upstream模块实现负载均衡。我们简单修改C:\nginx-1.16.1\conf\nginx.conf就好：

注意：别被下面大文件吓住，其实修改点很少，我用粗体标识出来了：

#user  nobody;
worker_processes  1;

#error_log  logs/error.log;
#error_log  logs/error.log  notice;
#error_log  logs/error.log  info;

#pid        logs/nginx.pid;

events {
    worker_connections  1024;
}

http {
    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;

    sendfile        on;
    #tcp_nopush     on;

    #keepalive_timeout  0;
    keepalive_timeout  65;

    #gzip  on;

    upstream firstdemo{
        server 127.0.0.1:8080;
        server 127.0.0.1:3000;
    }

    server {
        listen       80;
        server_name  localhost;

        #charset koi8-r;

        #access_log  logs/host.access.log  main;

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

        #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;
    #    }
    #}

}

上面粗红体表示代理到firstdemo上。

粗蓝体则表示由8080和3000的端口分别对localhost:80的请求提供http服务。

之后使用C:\nginx-1.16.1>nginx.exe -s reload 重启nginx服务，在浏览器里输入localhost，再不断刷新，就可以轮换看到以下画面了：

这样每次刷新就会访问不同的服务器，至此我们实现了一个简单的负载均衡。

只启动一个比如3000的node server，不断刷新浏览器，然后再启动一个比如8080的tomcat，效果是什么样的诸位看官可以自行尝试一下。

--END-- 2019年12月14日06:37:45