Docker模拟Nginx负载均衡

• 直接上dockerfile
• 目录结构：

├── build
│   ├── lb1
│   │   └── Dockerfile
│   ├── lb2
│   │   └── Dockerfile
│   └── slb
│       ├── Dockerfile
│       └── default.conf
└── docker-compose.yml

• vim build/lb1/Dockerfile

FROM daocloud.io/library/nginx:1.13.0-alpine
RUN echo "I am web1" > /usr/share/nginx/html/index.html

• vim build/lb2/Dockerfile

FROM daocloud.io/library/nginx:1.13.0-alpine
RUN echo "I am web2" > /usr/share/nginx/html/index.html

• vim build/slb/Dockerfile

FROM daocloud.io/library/nginx:1.13.0-alpine
RUN mv /etc/nginx/conf.d/default.conf /etc/nginx/conf.d/default.conf.bak
COPY default.conf /etc/nginx/conf.d/default.conf

• vim build/slb/default.conf

upstream allserver {
    server lb1;
    server lb2;
}
server {
    listen 80;
    server_name  localhost;
    location / {
      proxy_pass http://allserver;
    }
}

• vim docker-compose.yml

version: '2.3'

services:

  slb:
      build:
        context: ./build/slb
      privileged: true
      ports:
        - "8080:80"
      links:
        - "lb1"
  lb1:
      build:
        context: ./build/lb1
      privileged: true
      ports:
        - "8081:80"
  lb2:
      build:
        context: ./build/lb2
      privileged: true
      ports:
        - "8082:80"

启动服务并在后台运行, 在 docker-compose.yml 所在目录执行：

docker-compose up  -d

查看容器是否启动运行

docker ps -a

测试, 执行多次观察输出结果

curl  localhost:8080

输出结果：

I am web1

I am web2