Docker下Nginx+Tomcat实现负载均衡

Docker上配置负载均衡，启动一个nginx容器，三个tomcat容器。

结构如下：

配置步骤

1.在宿主机上安装docker并启动

2.拉取nginx、tomcat镜像，默认拉取最新的

docker pull tomcat
docker pull nginx
3.启动tomcat镜像并创建新首页

docker run -d -p 8081:8080 --name tomcat1 tomcat
docker run -d -p 8082:8080 --name tomcat2 tomcat
docker run -d -p 8083:8080 --name tomcat3 tomcat
配置新首页

vi index.html

hello hello

三个容器分别执行

docker cp index.jsp tomcat1:/usr/local/tomcat/webapps/ROOT/index.html
docker cp index.jsp tomcat2:/usr/local/tomcat/webapps/ROOT/index.html
docker cp index.jsp tomcat3:/usr/local/tomcat/webapps/ROOT/index.html
4.准备nginx.conf配置文件

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;

 

upstream tomcat {
server 192.168.179.132:8081 weight=1;
server 192.168.179.132:8082 weight=5;
server 192.168.179.132:8083 weight=3;
}
server {
listen 80;
server_name localhost;
location / {
proxy_pass http://tomcat;

}
}

include /etc/nginx/conf.d/*.conf;
}

然后将nginx.conf 从本地放到容器里

docker cp nginx.conf nginx:/etc/nginx/nginx.conf

5.重启nginx容器

docker restart nginx

6.检查上述容器是否正常启动，并关闭防火墙或者开启80、8081、8082、8083端口

7.测试

如上述都正确配置，即可进行测试

[root@docker ~]# while true; do wget -O - -q http://192.168.0.130:82;sleep 3; done
this is tomcat3
this is tomcat2
this is tomcat1
this is tomcat3
this is tomcat2
出现如上，说明设置成功。