Installing Docker

1. It is absolutely necessary to make sure that no Docker components have already been installed on this OS:

    sudo apt purge docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin
   

2. Add the official Docker repository to get the latest Docker version (as Debian repositories have an older version of Docker):
   1. Install Pre-requisites:

       sudo apt update && sudo apt install ca-certificates curl gnupg
      

   2. Create a directory to store GPG keys:

       sudo install -m 0755 -d /etc/apt/keyrings
      

   3. Download the Docker GPG key and store it in the new directory:

       curl -fsSL https://download.docker.com/linux/debian/gpg | sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg
      

   4. Change the permissions of the GPG key:

       sudo chmod a+r /etc/apt/keyrings/docker.gpg
      

   5. Add the official Docker repository:

       echo \
         "deb [arch="$(dpkg --print-architecture)" signed-by=/etc/apt/keyrings/docker.gpg] https://download.docker.com/linux/debian \
         "$(. /etc/os-release && echo "$VERSION_CODENAME")" stable" | \ tee /etc/apt/sources.list.d/docker.list > /dev/null
      

   6. Update from the Docker repo and install Docker:

       sudo apt update && sudo apt-get install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin
      

   7. Test the Docker installation with a “hello world” container:

       sudo docker run hello-world
      

   8. If the “hello world” container ran successfully, the following output will be displayed:

       Hello from Docker!
       This message shows that your installation appears to be working correctly.
      

Create a Docker group and Add a user

NOTE: By default, Docker requires root permissions to manage containers. Therefore, a user must use sudo with every Docker command. This can get annoying, so adding the user to the “docker” group will mitigate this.

1. Create a docker group:

    sudo groupadd docker
   

2. Add the user to the group:

    sudo usermod -aG docker <non_root_username>
   

3. Log out and log back in again as the non-root user.
4. Test with “hello world”:

    docker run hello-world
   

References

https://itsfoss.com/debian-install-docker/ https://www.simplilearn.com/tutorials/docker-tutorial/how-to-install-docker-on-ubuntu https://www.digitalocean.com/community/tutorials/how-to-install-and-use-docker-on-ubuntu-22-04

Docker Commands

https://docs.docker.com/engine/reference/commandline https://docs.linuxserver.io/general/docker-compose