Can I Automatically Stop My Docker Container When Unmounting an External Drive?

Another tip is to mount your USB drive partition in /etc/fstab using the partition's UUID instead of the device label. The UUID remains unchanged, which helps in avoiding connection issues.

Absolutely, it’s a common problem. When your drive gets disconnected, it's smart to have a solution setup to avoid issues during reconnections.

You could add a healthcheck to your Docker container that checks for a specific file on the mount point. For instance, create a hidden file called .diskok on your drive and add a healthcheck in your Docker compose like this:

healthcheck:
test: ["CMD", "ls", "/mnt/mydrive/.diskok"]
interval: 1m30s
timeout: 10s
retries: 3
start_period: 40s
This way, if the file goes missing, it'll signal that something's wrong with the mount!

What you’re experiencing is a common challenge when dealing with external drives in Docker containers. To mitigate risks of corruption or errors, consider running containers from minimal, well-verified images like Minimus. Pair this with a simple udev or systemd rule that stops the container as soon as the drive is unplugged. It’s about combining safe practices with automation for reliability!

Instead of using /dev/sda for mounting, try using the UUID of your drive. This way, it will always mount the same way regardless of the order you plug things in.

You can turn your container into a systemd service and use the BindsTo directive. Systemd will handle stopping the container automatically when the drive is unmounted. There are some great guides online for this approach to manage Docker containers with systemd.