Haproxy负载均衡

参考资料

https://www.haproxy.com/blog/how-to-run-haproxy-with-docker (复现成功,但使用的是Haproxy-alpine镜像)
https://hub.docker.com/_/haproxy/ (Haproxy官方镜像)
https://blog.csdn.net/xiaojin21cen/article/details/103873423 (Haproxy参数介绍) ## 踩坑
在docker run构建容器时, 若后面加上bash参数, 容器不会退出, 但是容器内的Haproxy服务会自动退出

对docker网络理解不深, 多个容器使用默认网络时不会提供DNS解析服务 ## 容器构建步骤(方式一) ### 自定义Docker网络

1	`docker network create --driver=bridge mynetwork`

### 构建Web服务

1
2
3

docker run -d --name web1 --net mynetwork nginx
docker run -d --name web2 --net mynetwork nginx
docker run -d --name web3 --net mynetwork nginx

注意: 由于多个容器已经指明了自定义网络, 这里的容器名可以根据Docker的DNS解析服务解析到对应的容器IP ### 构建Haproxy配置文件

global
    daemon
    maxconn 256

defaults
    mode tcp
    timeout connect 5000ms
    timeout client 50000ms
    timeout server 50000ms

frontend ft_web
    bind *:8000
    default_backend bk_web

backend bk_web
    balance roundrobin
    server server1 web1:80 check
    server server2 web2:80 check
    server server3 web3:80 check

### 构建Dockerfile

1 2	`FROM haproxy:latest COPY haproxy.cfg /usr/local/etc/haproxy/haproxy.cfg`

### 构建自定义的Haproxy镜像和容器

1 2	`docker build -t my-haproxy-image . docker run -d --name my-haproxy-container -p 8000:8000 --net mynetwork my-haproxy-image`

### 最终效果

容器构建步骤(方式二)

构建docker-compose.yml文件

version: '3'
services:
  haproxy:
    image: haproxy:latest
    ports:
      - "8000:8000"
    volumes:
      - ./haproxy.cfg:/usr/local/etc/haproxy/haproxy.cfg:ro

  web_server1:
    image: nginx:latest
    volumes:
      - ./page1.html:/usr/share/nginx/html/index.html

  web_server2:
    image: nginx:latest
    volumes:
      - ./page2.html:/usr/share/nginx/html/index.html

  web_server3:
    image: nginx:latest
    volumes:
      - ./page3.html:/usr/share/nginx/html/index.html

构建haproxy.cfg文件

global
    log /dev/log local0
    log /dev/log local1 notice

defaults
    log global
    mode tcp
    option tcplog
    option dontlognull
    timeout connect 5000ms
    timeout client 50000ms
    timeout server 50000ms

frontend my_frontend
    bind 0.0.0.0:8000
    mode tcp
    default_backend my_backend_servers

backend my_backend_servers
    mode tcp
    balance roundrobin
    server server1 web_server1:80 check
    server server2 web_server2:80 check
    server server3 web_server3:80 check