采用nginx让多个tomcat实现负载均衡

灰太狼 2022-08-20 15:09 186阅读 0赞

由于目录已将项目正式部署并发布了，但由于时不时地会出现bug，修复bug再次提交后，会让项目出现短时间的无法访问的问题，虽然时间虽短，但还是会影响用户的体验。为了不让用户察觉出项目的变动，于是我便采用了用nginx来实现负载均衡,主要步骤记录如下：

# 1.配置nginx安装源 #

**vim /etc/yum.repos.d/nginx.repo **  
\#nginx.repo

<span style="white-space:pre">	</span>[nginx]  
    	name=nginx repo  
    	baseurl=http://nginx.org/packages/centos/7/$basearch/  
    	gpgcheck=0  
    	enabled=1

# 2.安装nginx #

如已安装了nginx，需要升级，执行update即可  
**yum update nginx**

如未安装，执行如下命令，安装即可

**yum install nginx -y**

nginx -v //查看版本

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![Center 1][]

# 3.查看nginx的安装目录 #

#  whereis nginx #

# 4.编辑nginx配置文件 #

**cd /etc/nginx **

**vim nginx.conf**

在此，附上nginx.conf的源码:

user  nginx;
    worker_processes  1;
    
    error_log  /var/log/nginx/error.log warn;
    pid        /var/run/nginx.pid;
    
    
    events {
        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;
        #tcp_nopush     on;
    
        keepalive_timeout  65;
    
        #gzip  on;
    
        include /etc/nginx/conf.d/*.conf;
    }

从上面可以看出，还调用了/etc/nginx.conf.d/\*.conf文件

![Center 2][]

再附上default.conf源码：

upstream school {
    	server 192.168.1.103:80;
    	server 192.168.1.100:8080;
    	server 192.168.1.101:80;
    }
    
    server {
        listen       80;
        server_name  school;
    
        #charset koi8-r;
        #access_log  /var/log/nginx/log/host.access.log  main;
    
        location / {
           # root   /usr/share/nginx/html;
    
    	proxy_pass http://school;	
    
          #  index  index.html index.htm;
        }
    
        #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;
        }
    
    }

如此一来，就完成了3台服务器的简单负载了。

# 5.测试nginx配置是否正确 #

**nginx -t**

**![Center 3][]**

都显示的ok和successful表示配置没得什么问题

# 6.启动nginx #

启动下nginx就可以了

**service nginx start**

再输入nginx的地址测试一下：

![Center 4][]

![Center 5][]

由此看出，每执行一次,所到达的tomcat服务都是不一样的，OK！大功告成!!!

另附上在我们的生产环境中常用到的基于域名的配置：

这种常见的为解决这种情况,多个域名都指向同一个IP，在浏览器上输入不同的域名，跳转到不同的目录下。

配置源码如下：

worker_processes  1;
    
    events {
        worker_connections  1024;
    }
    
    http {
        include       mime.types;
        default_type  application/octet-stream;
    
      
        sendfile        on;
        keepalive_timeout  65;
    
        upstream www.xxx.com.cn{
    	server 127.0.0.1:8080;
        }
    
        upstream xxx.com.cn{
    	server 127.0.0.1:9090;
        }
    
        upstream wx.xxx.com.cn{
    	server 127.0.0.1:9527;
        }
    
        upstream test.xxx.com.cn{
    	server 127.0.0.1:8091;
        }
    
    
    
        server {
            listen       80;
            server_name  www.xxx.com.cn;
    
            location / {
                proxy_pass   http://www.xxx.com.cn;
                index  index.html index.htm;
            }
        }
    
        server {
            listen       80;
            server_name  xxx.com.cn;
    
            location / {
                proxy_pass   http://xxx.com.cn;
                index  index.html index.htm;
            }
        }
    
        server {
            listen       80;
            server_name  wx.xxx.com.cn;
    
            location / {
                proxy_pass   http://wx.xxx.com.cn;
                index  index.html index.htm;
            }
        }
    
        server {
            listen       80;
            server_name  test.xxx.com.cn;
    
            location / {
                proxy_pass   http://test.xxx.com.cn;
                index  index.html index.htm;
            }
        }
    
    }

[Center]: /images/20220731/338a6f84ff704184812185b0ea859c36.png
[Center 1]: /images/20220731/0b541a62fe554c32b79bed5451afb985.png
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