What This Error Means
Docker cannot remove the container filesystem because the device is busy, usually due to running processes, mounts, or lingering references.
How to Fix It
Find containers using the resource:docker ps -a (then inspect mounts as needed).
Stop/remove the container(s), then retry removal.
If the daemon is stuck, restart Docker and retry.
Why It Happens
A running container is still using the volume/filesystem layer.
A previous container left a stale mount or a stuck process.
The host OS is holding file locks (more common on desktop environments).
How to Verify
Retry the remove command and confirm it succeeds.
Confirm the resource no longer appears in docker volume ls / docker ps -a.
Examples
Error: Unable to remove filesystem for <container-id>: Device or resource busy Prevention Tips
Clean up containers and volumes as part of CI teardown.
Avoid sharing volumes across many long-lived containers without clear ownership.