How to fix Error response from daemon: container already started in Docker

DockerBEGINNERLOWUpdated Dec 6, 2025· 233 views

This error occurs when you attempt to start a Docker container that is already running. The fix is simple: either use the existing running container, restart it, or stop and remove it before creating a new one.

Quick fix

Fixes Error response from daemon: container already started

docker ps -a
  1. Check the container's current state
  2. Use the running container directly
  3. Restart the container if needed
  4. Stop the container if you need to recreate it
docker — error
docker ps -a
Error response from daemon: container already started

What this error means

When you run `docker start <container>` on a container that is already in a running state, Docker returns the "container already started" error. This is Docker's way of preventing duplicate container instances and protecting against potential resource conflicts. Every Docker container has a lifecycle with states like "created", "running", "paused", "stopped", and "dead". The `docker start` command is designed to transition a stopped container to the running state. When you issue this command against a container that's already running, Docker rightfully rejects the operation since the container cannot be "started" twice. This error is informational rather than critical - it's telling you that what you're trying to do is already done. The container is already running and ready to use.

Typical symptoms

  • Running 'docker start <container>' returns 'container already started'
  • Scripts or automation that call docker start fail unexpectedly
  • CI/CD pipelines report container start failures
  • Docker Compose operations report containers are already running
  • Container orchestration scripts exit with error codes

Common causes

  1. The container is already running from a previous docker start or docker run command
  2. A background process or another terminal session started the container
  3. Docker Compose or another orchestration tool started the container
  4. Container was configured with restart policy and auto-started after system reboot
  5. Script logic doesn't check container state before attempting to start

How to fix "Error response from daemon: container already started"

1Check the container's current state

First, verify whether the container is actually running:

List all containers (including stopped ones):

bash
docker ps -a

Check a specific container:

bash
docker inspect --format='{{.State.Status}}' <container_name_or_id>

If the status shows "running", the container is already active and you can use it directly. Common states include:
- running - Container is active
- exited - Container has stopped
- created - Container exists but never started
- paused - Container is paused

2Use the running container directly

If the container is already running, you don't need to start it again. Simply use it:

Execute commands in the running container:

bash
docker exec -it <container_name> /bin/bash
# Or for Alpine/minimal images:
docker exec -it <container_name> /bin/sh

View container logs:

bash
docker logs <container_name>
# Follow logs in real-time:
docker logs -f <container_name>

Check container resource usage:

bash
docker stats <container_name>

The container is already available for your workload.

3Restart the container if needed

If you need to restart the container (e.g., to pick up configuration changes), use the restart command instead of start:

bash
docker restart <container_name>

This command stops and then starts the container in one operation. It's safe to run on both running and stopped containers.

With a timeout (default is 10 seconds):

bash
docker restart -t 30 <container_name>

This gives the container 30 seconds to gracefully shut down before being forcefully stopped.

4Stop the container if you need to recreate it

If you want to stop the running container before making changes:

Stop gracefully:

bash
docker stop <container_name>

Force stop immediately:

bash
docker kill <container_name>

After stopping, you can start it again:

bash
docker start <container_name>

Or remove it entirely and create a new one:

bash
docker rm <container_name>
docker run --name <container_name> <image>
5Handle container start in scripts safely

To make scripts idempotent and avoid this error, check container state before starting:

Bash one-liner to start only if not running:

bash
docker start <container_name> 2>/dev/null || true

More robust script pattern:

bash
#!/bin/bash
CONTAINER_NAME="mycontainer"

# Check if container exists and is running
if [ "$(docker inspect -f '{{.State.Running}}' $CONTAINER_NAME 2>/dev/null)" = "true" ]; then
    echo "Container is already running"
else
    # Start existing container or create new one
    docker start $CONTAINER_NAME 2>/dev/null || \
    docker run -d --name $CONTAINER_NAME myimage:latest
fi

Alternative using docker ps:

bash
if ! docker ps --format '{{.Names}}' | grep -q "^${CONTAINER_NAME}$"; then
    docker start $CONTAINER_NAME
fi

Advanced notes

### Container Lifecycle States

Understanding Docker container states helps prevent this and similar errors:

| State | Description | Valid Operations |
|-------|-------------|------------------|
| created | Container exists but never started | start, rm |
| running | Container is actively running | stop, kill, pause, exec, restart |
| paused | Container is paused | unpause |
| exited | Container has stopped | start, rm |
| dead | Container failed to stop properly | rm -f |

### Using Docker Compose

With Docker Compose, use these commands to manage container states properly:

bash
# Start services (handles already-running gracefully)
docker compose up -d

# Restart a specific service
docker compose restart <service_name>

# Stop and remove containers
docker compose down

# View service status
docker compose ps

Docker Compose is more forgiving than raw Docker commands and handles already-running containers gracefully.

### Container Restart Policies

If your container keeps auto-starting, check its restart policy:

bash
docker inspect --format='{{.HostConfig.RestartPolicy.Name}}' <container>

Restart policies:
- no - Never restart (default)
- always - Always restart when stopped
- unless-stopped - Restart unless manually stopped
- on-failure - Restart only on non-zero exit code

To change the restart policy of an existing container:

bash
docker update --restart=no <container_name>

### Idempotent Container Management

For production scripts and CI/CD pipelines, design commands to be idempotent:

bash
# This pattern is safe to run multiple times
docker rm -f mycontainer 2>/dev/null || true
docker run -d --name mycontainer myimage:latest

Or use Docker Compose which is inherently more idempotent for managing application stacks.

Frequently asked questions

What does "Error response from daemon: container already started" mean?
When you run docker start <container> on a container that is already in a running state, Docker returns the "container already started" error. This is Docker's way of preventing duplicate container instances and protecting against potential resource conflicts. Every Docker container has a lifecycle with states like "created", "running", "paused", "stopped", and "dead".
How do I fix "Error response from daemon: container already started"?
This error occurs when you attempt to start a Docker container that is already running. The fix is simple: either use the existing running container, restart it, or stop and remove it before creating a new one.
What causes "Error response from daemon: container already started"?
The container is already running from a previous docker start or docker run command A background process or another terminal session started the container Docker Compose or another orchestration tool started the container
Is the "Error response from daemon: container already started" error serious?
It is a low-severity error — more of a blocker than a risk. The steps above resolve it.

Official resources & further reading