====== Docker setup ======

Setup procedure from source: [[https://docs.docker.com/engine/install/debian/]]\\

===== Instalation =====

//This installation process DO NO use the standard Debian repositories.\\
From Debian 11 it seems the standard repositories include Docker (docker.io) and docker-compose. However, the official versions are several versions behind Docker official releases. Since Docker is still a fast evolving tool, it is meaningful to get more up to date versions...//\\

==== Docker Engine ====
  * Remove previous docker versions:
''$ sudo apt-get remove docker docker-engine docker.io containerd runc''\\

  * Update packages:
''$ sudo apt-get update''\\

  * Install docker required packages:
''$ sudo apt-get install \
    apt-transport-https \
    ca-certificates \
    curl \
    gnupg-agent \
    software-properties-common''\\

  * Add docker GPG key:
''$ curl -fsSL https://download.docker.com/linux/debian/gpg | sudo apt-key add -''\\

  * Check key:
''$ sudo apt-key fingerprint 0EBFCD88''\\

  * Add docker repository:
''$ sudo add-apt-repository \
   "deb [arch=amd64] https://download.docker.com/linux/debian \
   $(lsb_release -cs) \
   stable"''\\

  * Change debian release name if docker doesn't offer a release for the current version (docker might not provide a release for debian testing...):
//THIS IS DANGEROUS//\\
update the docker line in /etc/apt/sources.list\\

  * Install docker:
''$ sudo apt-get update''\\
''$ sudo apt-get install docker-ce docker-ce-cli containerd.io''\\

  * Test docker with hello world container:
''$ sudo docker run hello-world''

  * Run docker at startup:
''$ sudo systemctl enable docker''\\

  * Display docker version:
''$ docker --version''\\


==== Docker Compose ====

Latest version here: [[https://github.com/docker/compose/releases/latest]]\\

  * Install docker-compose:
Replace the version number by the current latest official release found above, and run the commands:\\
''$ sudo curl -L "https://github.com/docker/compose/releases/download/1.25.5/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose''\\
''$ sudo chmod +x /usr/local/bin/docker-compose''\\

Check installed version:\\
''$ docker-compose --version''\\

===== Configuration =====

==== Limit docker resources usage ====
It is possible to set resources limits using docker-compose, without starting a swarm service.\\
This feature was previously available in version 2 of compose-file. Since version 3, a new "deploy" section has been set up, normally only for 'docker stack deploy' feature, but then a --compatibility mode was added to docker-compose, so that it does not ignore information in the "deploy" section.\\

To run a docker-compose.yml file above version 3 with resource limits, just run it like:\\
''$ sudo docker-compose --compatibility -f docker-compose.yml up -d''\\