docker-ubuntu.md

Here's a terminal guide to pull the Docker Ubuntu image and run it from the terminal in macOS:

1. Install Docker Desktop:

• Download Docker Desktop for Mac from https://www.docker.com/products/docker-desktop
• Follow the installation instructions, which typically involve dragging the Docker icon to your Applications folder and starting it.

2. Pull the Ubuntu image:

• Open a terminal window (Applications > Utilities > Terminal).
• Run the following command to pull the latest Ubuntu image:

docker pull ubuntu

3. Run the Ubuntu container:

• Execute the following command to start an interactive Ubuntu container:

docker run -it ubuntu /bin/bash

Explanation of flags:

• -it: Allocates a pseudo-TTY and keeps STDIN open, allowing interactive terminal use.
• ubuntu: Specifies the Ubuntu image to run.
• /bin/bash: Launches the Bash shell within the container.

4. Work within the container:

• You'll now be inside the Ubuntu container's Bash shell.
• Use Ubuntu commands as you would on a regular Ubuntu system.
• To exit the container, type exit.

Additional notes:

• To view running containers, use docker ps.
• To stop a container, use docker stop <container_id>.
• To remove a container, use docker rm <container_id>.
• To list available images, use docker images.
• To remove an image, use docker rmi <image_id>.

I'll provide instructions for reconnecting to the same terminal session in different scenarios:

1. Disconnected SSH session:

• If the session is still active on the server:

  • Open a new terminal window and use the same SSH command you used previously to connect.
  • You should be reconnected to the same session.

• If the session has terminated:

  • You'll need to start a new SSH session and resume your work.

2. Closed terminal window:

• Using terminal multiplexers (tmux or screen):
  • If you started the session within a terminal multiplexer, you can reattach to it using:
    • tmux attach
    • screen -r

3. Reconnecting within Docker:

• To reattach to a running Docker container:

  • Use the docker attach command:

    docker attach <container_id>

• To start a new interactive session in a running container:

  • Use the docker exec command:

    docker exec -it <container_id> /bin/bash

4. Reconnecting to a local terminal session:

• macOS Terminal app:
  • There's no built-in reconnection feature.
  • Consider using a terminal multiplexer like tmux or screen for persistent sessions.

5. Specific terminal emulators:

• Some terminal emulators might have their own reconnection features.
• Check the documentation for your specific emulator for details.

General tips:

• To prevent accidental disconnections, consider:
  • Using the -o ServerAliveInterval=60 option with SSH to send keep-alive messages.
  • Enabling terminal multiplexers like tmux or screen for persistent sessions.