Container Lifecycle

Containers move through created, running, paused, stopped and removed states, each with its own command.

Syntaxdocker start|stop|restart|rm CONTAINER

A container has a lifecycle. Knowing the states and the commands that move between them keeps your system tidy.

The core commands

  • docker create — make a container without starting it.
  • docker start — start a stopped container.
  • docker stop — gracefully stop a running container.
  • docker restart — stop then start again.
  • docker pause / docker unpause — freeze and resume processes.
  • docker rm — delete a stopped container.

Listing containers

docker ps shows running containers; add -a to include stopped ones.

Example

Example · bash
# List running containers, then all containers
docker ps
docker ps -a

# Stop, start and remove a container
docker stop web
docker start web
docker rm -f web   # -f force-removes even if running

# Remove all stopped containers
docker container prune

When to use it

  • An ops engineer stops a container gracefully with docker stop before deploying a new version, giving the app 10 seconds to finish in-flight requests.
  • A developer uses docker pause to freeze a container mid-process while taking a checkpoint, then resumes with docker unpause.
  • A CI pipeline creates containers with docker create and configures volumes before starting them with docker start, separating creation from execution.

More examples

Move through lifecycle states

Shows each lifecycle transition: create, start, stop, and remove, explicitly rather than using docker run.

Example · bash
# Create but don't start
docker create --name myapp myimage:latest

# Start the created container
docker start myapp

# Stop gracefully (SIGTERM, then SIGKILL after 10s)
docker stop myapp

# Remove stopped container
docker rm myapp

Pause and unpause a container

Freezes all processes in a container using cgroups freezer, then resumes them without losing state.

Example · bash
docker run -d --name worker myapp:latest
docker pause worker
docker ps  # STATUS shows "Paused"
docker unpause worker

Force-kill and check exit code

Sends SIGKILL to forcefully stop an unresponsive container, then checks the exit code for post-mortem analysis.

Example · bash
# Immediately kill (SIGKILL) without waiting
docker kill myapp

# Inspect why the container exited
docker inspect myapp --format '{{.State.ExitCode}} {{.State.Error}}'

Related

docker rundocker restart policies

Discussion

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