How to Run HAProxy with Docker

blog20210802-01.sh

$ sudo docker network create --driver=bridge mynetwork

blog20210802-02.sh

$ sudo docker run -d \
   --name web1 --net mynetwork jmalloc/echo-server:latest
   
$ sudo docker run -d \
   --name web2 --net mynetwork jmalloc/echo-server:latest
   
$ sudo docker run -d \
   --name web3 --net mynetwork jmalloc/echo-server:latest

blog20210802-03.sh

$ sudo docker ps

CONTAINER ID   IMAGE                        COMMAND              CREATED              STATUS              PORTS      NAMES
98216bb8c5ff   jmalloc/echo-server:latest   "/bin/echo-server"   About a minute ago   Up About a minute   8080/tcp   web3
ae6accc111d9   jmalloc/echo-server:latest   "/bin/echo-server"   About a minute ago   Up About a minute   8080/tcp   web2
554fafbc2b3b   jmalloc/echo-server:latest   "/bin/echo-server"   About a minute ago   Up About a minute   8080/tcp   web1

blog20210802-04.cfg

global
  stats socket /var/run/api.sock user haproxy group haproxy mode 660 level admin expose-fd listeners
  log stdout format raw local0 info

defaults
  mode http
  timeout client 10s
  timeout connect 5s
  timeout server 10s
  timeout http-request 10s
  log global

frontend stats
  bind *:8404
  stats enable
  stats uri /
  stats refresh 10s

frontend myfrontend
  bind :80
  default_backend webservers

backend webservers
  server s1 web1:8080 check
  server s2 web2:8080 check
  server s3 web3:8080 check

blog20210802-05.sh

$ sudo docker run -d \
   --name haproxy \
   --net mynetwork \
   -v $(pwd):/usr/local/etc/haproxy:ro \
   -p 80:80 \
   -p 8404:8404 \
   haproxytech/haproxy-alpine:2.4

blog20210802-06.sh

$ sudo docker ps

CONTAINER ID   IMAGE                            COMMAND                  CREATED          STATUS          PORTS                                        NAMES
d734d0ef2635   haproxytech/haproxy-alpine:2.4   "/docker-entrypoint.…"   3 seconds ago    Up 2 seconds    0.0.0.0:80->80/tcp, 0.0.0.0:8404->8404/tcp   haproxy

blog20210802-07.sh

$ sudo docker kill -s HUP haproxy

blog20210802-08.sh

$ sudo docker stop web1 && sudo docker rm web1
$ sudo docker stop web2 && sudo docker rm web2
$ sudo docker stop web3 && sudo docker rm web3
$ sudo docker stop haproxy && sudo docker rm haproxy
$ sudo docker network rm mynetwork