Where are other Docker variables stored?

Docker environment variables can be set and stored in various places depending on their intended use and scope. Here are some common locations where Docker-related environment variables might be stored:

1. Shell Configuration Files:

• .bashrc, .bash_profile, or .zshrc: These files are used to set environment variables for user sessions in Linux and macOS. You can add export commands here to make variables persistent across terminal sessions.
• Example:

  export DOCKER_HOST=tcp://192.168.99.100:2376
  

2. Docker Daemon Configuration:

• /etc/docker/daemon.json: This file is used to configure the Docker daemon. You can set various options here, but it's in JSON format rather than environment variables.
• Example:

  {
    "hosts": ["tcp://0.0.0.0:2376", "unix:///var/run/docker.sock"]
  }
  

3. System Environment Variables:

• You can set Docker-related environment variables at the system level, which will apply to all users and sessions. This is done through system configuration files or environment variable management tools, depending on the operating system.

4. Docker Compose Files:

• In Docker Compose, you can define environment variables in the docker-compose.yml file under the environment section for services.
• Example:

  services:
    web:
      image: my-web-app
      environment:
        - NODE_ENV=production
  

5. Container Environment Variables:

• When you run a container, you can pass environment variables directly using the -e flag with the docker run command.
• Example:

  docker run -e MY_VAR=value my-image
  

Summary:

Docker environment variables can be stored in user shell configuration files, Docker daemon configuration files, system environment variables, Docker Compose files, or passed directly to containers at runtime. The location depends on the scope and purpose of the variable.