The Docker command cheat sheet

Quick reference

Images

$docker images
$docker pull nginx:1.27
$docker build -t api:1.0 .
$docker history api:1.0
$docker inspect nginx:1.27

Containers

$docker ps -a
$docker run -d -p 8080:80 nginx
$docker logs -f --tail 100 api
$docker exec -it api sh
$docker stats --no-stream

Compose

$docker compose up -d
$docker compose ps
$docker compose logs -f api
$docker compose config
$docker compose down -v

Cleanup

$docker system df
$docker container prune
$docker image prune -a
$docker volume prune -a
$docker builder prune

Explained

Images

Start with images. docker images lists what is local, docker pull nginx:1.27 fetches a pinned tag, and docker build -t api:1.0 . builds from the Dockerfile in the current directory. docker history api:1.0 shows the layers, and docker inspect nginx:1.27 prints the JSON behind the tag.

Containers and Compose

docker ps -a shows running and stopped containers, and docker run -d -p 8080:80 nginx starts one in the background with a port mapped. docker logs -f --tail 100 api follows the last hundred lines, docker exec -it api sh opens a shell, and docker stats --no-stream gives one snapshot of CPU and memory. Compose uses the same verbs with a project: docker compose up -d, ps, logs -f api, config and down -v.

Cleanup

Cleanup is where the disk comes back: docker system df shows what is using space, and container prune, image prune -a, volume prune -a and builder prune each target one kind of leftover.

In one line

Check the disk

$docker system df