以Docker的网络管理，容器的IP设置为基础知识实现Nginx负载均衡
查看所有docker网络
docker network ls/*NETWORK ID NAME DRIVER SCOPEb832b168ca9a bridge bridge local373be82d3a6a composetest_default bridge locala360425082c4 host host local154f600f0e90 none null local*/// composetest_default 是上一篇介绍Compose时，docker-compose.yml文件所在的目录名，// 所以，用docker-compose创建的容器会默认创建一个以目录名为网络名的网络，并且是dridge（桥接）类型指定容器IP地址
官网文档地址：https://docs.docker.com/compo...
继续编写上一篇《12.使用Docker Compose容器编排工具》文章中的docker-compose.yml
version: "3"services: web1: container_name: web1 image: "centos:httpd" ports: - "8080:80" privileged: true volumes: - "/app/www/web1/:/var/www/html/" command: ['/usr/sbin/init'] networks: nginx-lsb: ipv4_address: 192.169.0.3 web2: container_name: web2 image: "centos:httpd" ports: - "8081:80" privileged: true volumes: - "/app/www/web2/:/var/www/html/" command: ['/usr/sbin/init'] networks: nginx-lsb: ipv4_address: 192.169.0.2networks: nginx-lsb: driver: bridge ipam: config: - subnet: 192.169.0.0/16使用docker-compose启动容器
docker-compose up -d查看容器是否启动，并确认是否创建了网络 nginx-lsb
// 可以查看当前docker-compose.yml配置的容器组里的容器状态docker-compose psdocker network ls/*NETWORK ID NAME DRIVER SCOPEb832b168ca9a bridge bridge local373be82d3a6a composetest_default bridge localde6f5b8df1c8 composetest_nginx-lsb bridge locala360425082c4 host host local154f600f0e90 none null local*/// 创建了nginx-lsb网络，命名是容器组项目的 文件名开头_网络名查看网络 nginx-lsb的详情
docker network inspect composetest_nginx-lsb// 详情里面可以看到使用这个网络的每个容器的ip如：/*... "Containers": { "039aa860ef04f20a7566fdc943fb4398a61d2ad6dd3e373b17c86ac778af89e3": { "Name": "web2", "EndpointID": "1bc206661179e65999015f132c2889d3d4365b8d42b8a89cf9c260016fedd5ee", "MacAddress": "02:42:c0:a9:00:02", "IPv4Address": "192.169.0.2/16", "IPv6Address": "" }, "437ad7a07da8e46c0abaf845c4b08425338009fbe972bde69478cf47c75c315b": { "Name": "web1", "EndpointID": "5a36e602a5364ee9ad06e9816d09e3966d56ebf06b9394ebc25b8bcee9546607", "MacAddress": "02:42:c0:a9:00:03", "IPv4Address": "192.169.0.3/16", "IPv6Address": "" } },...*/使用 env_file环境文件：
简单可以理解为：在docker-compose.yml中定义变量，引用在外部.env文件中进行变量定义
官方文档地址：https://docs.docker.com/compo...
// 还是在composetest目录中定义个 .env文件，用来存放变量web1_addr=192.169.0.2web2_addr=192.169.0.3// 修改docker-compose.yml文件，加入变量定义version: "3"services: web1: container_name: web1 image: "centos:httpd" ports: - "8080:80" privileged: true volumes: - "/app/www/web1/:/var/www/html/" command: ['/usr/sbin/init'] networks: nginx-lsb: ipv4_address: ${web1_addr} web2: container_name: web2 image: "centos:httpd" ports: - "8081:80" privileged: true volumes: - "/app/www/web2/:/var/www/html/" command: ['/usr/sbin/init'] networks: nginx-lsb: ipv4_address: ${web2_addr}networks: nginx-lsb: driver: bridge ipam: config: - subnet: 192.169.0.0/16重新启动composetest项目，并查看网络详情，确认容器ip是否设置成功
// 重新启动composetest项目docker-compose up -d// 查看网络详情docker network inspect composetest_nginx-lsb在composetest项目中添加一台nginx服务器作为负载均衡服务器
// 在.env文件里添加一个变量 nginx_lsbweb1_addr=192.169.0.2web2_addr=192.169.0.3nginx_lsb=192.169.0.100// 修改docker-compose.yml文件，加入变量定义version: "3"services: nginx-lsb: container_name: nginx-lsb image: "centos:nginx" ports: - "8000:80" privileged: true volumes: - "/app/nginx/nginx.conf:/etc/nginx/nginx.conf" networks: nginx-lsb: ipv4_address: ${nginx_lsb} web1: container_name: web1 image: "centos:httpd" ports: - "8080:80" privileged: true volumes: - "/app/www/web1/:/var/www/html/" command: ['/usr/sbin/init'] networks: nginx-lsb: ipv4_address: ${web1_addr} web2: container_name: web2 image: "centos:httpd" ports: - "8081:80" privileged: true volumes: - "/app/www/web2/:/var/www/html/" command: ['/usr/sbin/init'] networks: nginx-lsb: ipv4_address: ${web2_addr}networks: nginx-lsb: driver: bridge ipam: config: - subnet: 192.169.0.0/16// 重新启动composetest项目docker-compose up -d修改nginx.conf配置文件，配置负载均衡
upstream mydocker { server 192.169.0.2; server 192.169.0.3;}server { listen 80； server_name mydocker; location / { 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_buffering off; proxy_pass http://mydocker; }}重新启动nginx-lsb，加载配置文件
docker-composer restart nginx-lsb访问 http://服务器IP地址:8000，测试服务器负载均衡！
注意：上一篇已经在两台httpd服务器上放置了不同的web文件
原文链接：http://www.mi360.cn/articles/20