CentOS7+Nginx配置Tomcat负载均衡环境

1.准备两个Tomcat

配置两个Tomcat一个端口是8080另外一个端口是8081，分别在webapps下面添加一个测试用的web项目，修改index.jsp文件，8080端口的index.jsp页面加入：

This page is from 8080 port

8081的端口的index.jsp加入：

This page is from 8081 port

之后启动两个Tomcat，8080端口跟8081端口都要开放

开放端口：
firewall-cmd --zone=public --add-port=8080/tcp --permanent

查看开放的端口:
firewall-cmd --list-ports

　　

2.配置Nginx

使用whereis nginx命令找到nginx所在的目录并进入目录内的conf文件夹找到ngnix.conf配置文件，在conf文件夹下创建一个vhosts文件夹并在里面创建一个webapp.conf文件内容如下：

upstream www.test.com {  #这里的名称要跟proxy_pass内的名称一致 

	server 127.0.0.1:8080 weight=1; #weight:权重，默认是1，数值越大提供服务的次数就越多 

	server 127.0.0.1:8081 weight=1; 

        server 127.0.0.1:8083 down; #down表示当前的服务暂不参于负载

        server 127.0.0.1:8084 backup; #backup 其它所有非backup机器down或者忙时，才会请求backup机器。
}  

server {
	listen 80;
	server_name www.test.com;
	access_log logs/bbs.access.log;
	error_log logs/bbs.error.log;
	#root html;
	#index index.html index.htm index.jsp index.php;  

	location / {
		proxy_pass http://www.test.com; #这里的http://www.test.com与上面的upstream要一样

		#Proxy Settings
		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;
		proxy_next_upstream error timeout invalid_header http_500 http_502 http_503 http_504;
		proxy_max_temp_file_size 0;
		proxy_connect_timeout 90;
		proxy_send_timeout 90;
		proxy_read_timeout 90;
		proxy_buffer_size 4k;
		proxy_buffers 4 32k;
		proxy_busy_buffers_size 64k;
		proxy_temp_file_write_size 64k;
	}
}  

接着将创建的vhosts/webapps.conf文件include到nginx.conf文件内。

#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;

    include vhosts/webapp.conf;#这里把webapp.conf文件include进来

    server {
        listen       80;
        server_name  localhost;

        #charset koi8-r;

        #access_log  logs/host.access.log  main;

        location / {
           root   html;
            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   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;
        #}
    }

重新加载Nginx:

./nginx -s reload

在地址栏输入地址看下效果：

把8080端口的Tomcat关闭后再访问：

3.随机启动

通过vi /lib/systemd/system/nginx.service来添加nginx.service文件，并输入如下内容：

[Unit]
Description=nginx 1.13.7
After=network.target  

[Service]
Type=forking
ExecStart=/usr/local/nginx/sbin/nginx
ExecReload=/usr/local/nginx/sbin/nginx -s reload
ExecStop=/usr/local/nginx/sbin/nginx -s quit
PrivateTmp=true  

[Install]
WantedBy=multi-user.target

注意：如果不是安装在/usr/local/nginx/目录下，请根据实际安装路径修改ExecStart、ExecReload、ExecStop中的值。

更改nginx.service为可执行：

chmod 755 /lib/systemd/system/nginx.service

设置开机自启动

systemctl enable nginx.service