docker.md

title	category	layout
Docker CLI	Devops	2017/sheet

Manage images

docker build

docker build [options] .
  -t "app/container_name"    # name
  --build-arg APP_HOME=$APP_HOME    # Set build-time variables

Create an image from a Dockerfile.

docker run

docker run [options] IMAGE
  # see `docker create` for options

Example

$ docker run -it debian:buster /bin/bash

Run a command in an image.

Manage containers

docker create

docker create [options] IMAGE
  -a, --attach               # attach stdout/err
  -i, --interactive          # attach stdin (interactive)
  -t, --tty                  # pseudo-tty
      --name NAME            # name your image
  -p, --publish 5000:5000    # port map (host:container)
      --expose 5432          # expose a port to linked containers
  -P, --publish-all          # publish all ports
      --link container:alias # linking
  -v, --volume `pwd`:/app    # mount (absolute paths needed)
  -e, --env NAME=hello       # env vars

Example

$ docker create --name app_redis_1 \
  --expose 6379 \
  redis:3.0.2

Create a container from an image.

docker exec

docker exec [options] CONTAINER COMMAND
  -d, --detach        # run in background
  -i, --interactive   # stdin
  -t, --tty           # interactive

Example

$ docker exec app_web_1 tail logs/development.log
$ docker exec -t -i app_web_1 rails c

Run commands in a container.

docker start

docker start [options] CONTAINER
  -a, --attach        # attach stdout/err
  -i, --interactive   # attach stdin

docker stop [options] CONTAINER

Start/stop a container.

docker ps

$ docker ps
$ docker ps -a
$ docker kill $ID

Manage containers using ps/kill.

docker logs

$ docker logs $ID
$ docker logs $ID 2>&1 | less
$ docker logs -f $ID # Follow log output

See what's being logged in an container.

Images

docker images

$ docker images
  REPOSITORY   TAG        ID
  ubuntu       12.10      b750fe78269d
  me/myapp     latest     7b2431a8d968

$ docker images -a   # also show intermediate

Manages images.

docker rmi

docker rmi b750fe78269d

Deletes images.

Clean up

Clean all

docker system prune

Cleans up dangling images, containers, volumes, and networks (ie, not associated with a container)

docker system prune -a

Additionally remove any stopped containers and all unused images (not just dangling images)

Containers

# Stop all running containers
docker stop $(docker ps -a -q)

# Delete stopped containers
docker container prune

Images

docker image prune [-a]

Delete all the images

Volumes

docker volume prune

Delete all the volumes

Also see

• Getting Started (docker.io)