Container
https://hub.docker.com/_/haproxy

Configuration
/tmp/haproxy/haproxy.cfg

global
  maxconn 4096
  #stats timeout 30s
  #debug

defaults
  log global
  mode http
  option httplog
  option dontlognull
  timeout connect 5000
  timeout client 50000
  timeout server 50000
  log 127.0.0.1 local0
  #option httpchk

frontend frontend1
  bind :80
  mode http
  use_backend backend1

backend backend1
  mode http
  balance roundrobin
  option httpchk GET / HTTP/1.1
  http-check expect status 400
  server www1 172.17.0.2:80 check
  server www2 172.17.0.4:80 check
  server www3 172.17.0.6:80 check

listen stats 
  bind :9000
  mode http
  stats enable
  stats hide-version
  stats realm Haproxy\ Statistics
  stats refresh 60s
  stats show-node
  stats auth haproxy:password
  stats uri /

Deploy

docker run -d --name haproxy -v /tmp/haproxy:/usr/local/etc/haproxy:ro -p 8080:80 -p 9000:9000 haproxy:latest
docker logs -f  haproxy

Create required directories

mkdir -p /etc/docker/nginx/{conf.d,html}

Configure nginx as webserver

cat < /etc/docker/nginx/conf.d/default.conf
server {
    listen 80;
    server_name _;

    root   /usr/share/nginx/html; 
    index  index.html index.htm;
}
EOF

Configure nginx as proxy

cat < /etc/docker/nginx/conf.d/proxy.conf
server {
    listen 80;
    server_name foo.example.com;

    location / {
        proxy_pass http://localhost:8080/;
    }
}
EOF

Create container

sudo docker run -d \
  --name nginx \
  --net host \
  -v /etc/docker/nginx/html:/usr/share/nginx/html:ro \
  -v /etc/docker/nginx/conf.d:/etc/nginx/conf.d:ro \
  nginx

debug

docker restart nginx
docker logs nginx -f

Links
https://hub.docker.com/_/nginx

Start container

docker run --name=roundcube \
  -e ROUNDCUBEMAIL_DEFAULT_HOST=imap.example.com \
  -e ROUNDCUBEMAIL_SMTP_SERVER=smtp.example.com \
  -e ROUNDCUBEMAIL_SMTP_PORT=993 \
  -p 8080:80 \
  -d  roundcube/roundcubemail

UI
http://SERVER_IP:8080/

Links
https://hub.docker.com/r/roundcube/roundcubemail/

Install Docker
https://docs.docker.com/engine/install/ubuntu/#install-using-the-repository

# Add Docker's official GPG key:
sudo apt-get update
sudo apt-get install ca-certificates curl
sudo install -m 0755 -d /etc/apt/keyrings
sudo curl -fsSL https://download.docker.com/linux/ubuntu/gpg -o /etc/apt/keyrings/docker.asc
sudo chmod a+r /etc/apt/keyrings/docker.asc

# Add the repository to Apt sources:
echo \
  "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.asc] https://download.docker.com/linux/ubuntu \
  $(. /etc/os-release && echo "${UBUNTU_CODENAME:-$VERSION_CODENAME}") stable" | \
  sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
sudo apt-get update

# Install the latest Docker version
udo apt-get install -y docker-ce #docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin

docker info

Deploy Docker CE with Ansible

- name: Install Docker
  become: true
  block:
    - name: Download Docker repository key
      get_url:
        url: https://download.docker.com/linux/ubuntu/gpg
        dest: /etc/apt/keyrings/docker.asc
        mode: '0644'

    - name: Add Docker repository
      ansible.builtin.apt_repository:
        repo: "deb [signed-by=/etc/apt/keyrings/docker.asc] https://download.docker.com/linux/ubuntu {{ ansible_lsb.codename }} stable"
        update_cache: yes

    - name: Install docker-ce
      apt:
        name: docker-ce

Deprected

wget -qO- https://raw.githubusercontent.com/panticz/installit/master/install.docker.sh | sudo bash

[embed_url: https://raw.githubusercontent.com/panticz/installit/master/install.docker.sh]

Enable Remote API
https://docs.docker.com/config/daemon/systemd/