This error occurs when you attempt to stop or kill a Docker container that has already exited. It's a harmless informational message indicating the container is not in a running state and doesn't require stopping.
This error message appears when you run `docker stop` or `docker kill` on a container that is already in a stopped or exited state. Docker containers can only be stopped when they're actually running. When a container has already exited (either normally or due to an error), attempting to stop it again will trigger this error. The error is typically not a problem—it's simply Docker's way of informing you that the requested operation (stopping a running container) doesn't apply to the current state of the container. The container might have stopped on its own, been stopped by another process, or crashed before you attempted to stop it. Understanding container states is key: a container can be in states like "running," "exited," "paused," or "restarting." The stop and kill commands only work on containers in the "running" state.
First, verify whether the container is actually running:
docker psThis shows only running containers. If your container doesn't appear here, it's not running.
To see all containers including stopped ones:
docker ps -aLook for your container in the list. The STATUS column will show something like "Exited (0) 2 minutes ago" if it's stopped.
If the container is already stopped and you want to remove it entirely:
docker rm <container_id_or_name>If the container is somehow stuck or you want to force removal:
docker rm -f <container_id_or_name>The -f flag will force removal even if the container is in an unusual state.
When writing automation scripts, filter for running containers only:
# Stop all running containers (safe approach)
docker stop $(docker ps -q)The -q flag lists only IDs, and docker ps without -a shows only running containers.
For conditional stopping in scripts:
# Check if container is running before stopping
if [ "$(docker inspect -f '{{.State.Running}}' container_name 2>/dev/null)" == "true" ]; then
docker stop container_name
else
echo "Container is not running, skipping stop"
fiTo remove all stopped containers at once:
docker container pruneDocker will ask for confirmation before removing stopped containers. To skip confirmation:
docker container prune -fThis is useful for regular maintenance and freeing up disk space.
Idempotent Operations: The docker stop command is designed to be idempotent in most use cases. If you need truly idempotent behavior in scripts (no error on already-stopped containers), use conditional checks or redirect stderr.
Docker Compose: When using Docker Compose, docker-compose down handles both stopping and removing containers gracefully, regardless of their current state. This is often safer for multi-container applications.
Container State Machine: Docker containers follow a state machine: created → running → paused/stopped → removed. Understanding this flow helps prevent these errors. You can inspect detailed state with docker inspect <container_id> | jq '.State'.
Systemd Integration: If you've configured containers to run as systemd services, stopping via docker stop might cause the service to restart the container immediately. Always stop the systemd service first: systemctl stop docker-<container_name>.service.
Race Conditions: In distributed systems or when multiple administrators manage the same Docker host, race conditions can occur where a container is stopped between your status check and stop command. Always handle this error gracefully in production scripts.
dockerfile parse error line 5: unknown instruction: RRUN
How to fix 'unknown instruction' Dockerfile parse error in Docker
Error response from daemon: manifest for nginx:nonexistent not found: manifest unknown: manifest unknown
How to fix 'manifest for image:tag not found' in Docker
Error response from daemon: invalid reference format: repository name must be lowercase
How to fix 'repository name must be lowercase' in Docker
Error response from daemon: No such image
How to fix 'No such image' in Docker
Error response from daemon: Container is not running
How to fix 'Container is not running' when using docker exec