Docker-Cheatsheet

First of all, thanks to these great cheat sheets.

• wsargent/docker-cheat-sheet
• drminnaar/cheatsheets

Dockerfile

The configuration file. Sets up a Docker container when you run docker build on it. Vastly preferable to docker commit.

Instructions

• .dockerignore
• FROM Sets the Base Image for subsequent instructions.
• MAINTAINER (deprecated - use LABEL instead) Set the Author field of the generated images.
• RUN execute any commands in a new layer on top of the current image and commit the results.
• CMD provide defaults for an executing container.
• EXPOSE informs Docker that the container listens on the specified network ports at runtime. NOTE: does not actually make ports accessible.
• ENV sets environment variable.
• ADD copies new files, directories or remote file to container. Invalidates caches. Avoid ADD and use COPY instead.
• COPY copies new files or directories to container. By default this copies as root regardless of the USER/WORKDIR settings. Use --chown=<user>:<group> to give ownership to another user/group. (Same for ADD.)
• ENTRYPOINT configures a container that will run as an executable.
• VOLUME creates a mount point for externally mounted volumes or other containers.
• USER sets the user name for following RUN / CMD / ENTRYPOINT commands.
• WORKDIR sets the working directory.
• ARG defines a build-time variable.
• ONBUILD adds a trigger instruction when the image is used as the base for another build.
• STOPSIGNAL sets the system call signal that will be sent to the container to exit.
• LABEL apply key/value metadata to your images, containers, or daemons.
• SHELL override default shell is used by docker to run commands.
• HEALTHCHECK tells docker how to test a container to check that it is still working.

Docker Commands

Docker info

Command	Description
docker version	provides full description of docker version
docker -v	provides a short description of docker version
docker info	display system wide information
docker info --format '{{.DriverStatus}}'	display 'DriverStatus' fragment from docker information
docker info --format '{{json .DriverStatus}}'	display 'DriverStatus' fragment from docker information in JSON format
docker version --format '{{.Server.Version}}'	display the server version

Images

Command	Description
docker images	shows all images
docker rmi $(docker images -q)	remove all images
docker rmi -f [image-name]	force remove an image by name
docker image rm [image-name]	remove image by name

Start a container

Command	Description
docker run --name [container-name] [image-name]	Specific container name
docker run --name [container-name] -d [image-name]	Specific container name, return container ID
docker run --name [container-name] -it [image-name]	Specific container name, access container shell
winpty docker run -it {Image name}	(Git Bash)
docker container run --rm [image-name]	Run container based on specified imaged and immediately remove it once it stops
docker run -it -v [volume-name]:[container-mount-path] [image-name]	Run container and bind mount volume

Containers

Command	Description
docker ps -a	List all containers
docker ps --filter status=running	Check container status which is running
docker stop $(docker ps --filter status=running -q)	Stop container which is running
docker stop $(docker ps -aq)	Stop all running containers
docker rm $(docker ps -aq)	Remove all containers
docker rm [container-ID]	Remove container by ID
docker rm [container-name]	Remove container by container name
docker exec -u 0 -it [container-ID] /bin/bash	Run a existing container, access container shell with user root

Volumes

Command	Description
docker volume create [volume-name]	Create volume
docker volume inspect [volume-name]	Display detailed information on one or more volumes
docker volume rm [volume-name]	Remove one or more volumes