Docker

Build

Build a container image

https://docs.docker.com/engine/reference/commandline/build/

If the current directory has a Dockerfile:

docker build -t IMAGE_NAME .

Run

Run a container from an image

https://docs.docker.com/engine/reference/commandline/run/

docker run FLAGS IMAGE_NAME [COMMANDS]

⚠ Make sure the flags come before the image name, otherwise they'll be interpreted as commands to run inside the container

Some helpful flags:

• --rm: Automatically delete the container when it's stopped
• -it: Use these when you will be connecting to the container (e.g. to run a shell)
• --network=host: Use the host machine's network instead of the default bridge network
  • This can be useful whenever the container is having problems accessing the network
• -v: Mount a directory from the host machine on the container, e.g. -v "$PWD:/build"
• -e: Set an environment variable, e.g. -e grails.env=dev
  • Or use --env-file to read in a .env file
• --name: When not using --rm, give the container a name which can be used to re-run it using docker start, e.g. docker start -a NAME

Restrict a container's resources

These parameters can be useful in specific situations such as trying to replicate issues in environments with constrained resources:

• --cpus
• --memory

e.g.

docker run -it --cpus="0.5" --memory="1g"

Containers

List running containers

docker container ls

List all containers

docker container ls --all

Connect to a terminal in a container

docker container exec -it CONTAINER_NAME_OR_ID sh

Stop a container

docker container stop CONTAINER_NAME_OR_ID

Delete a container

docker container rm CONTAINER_NAME_OR_ID

Images

List images

docker image ls

Clean up images

This will delete all images that don't have an associated container (you may want to delete any unused containers first--see above)

docker image prune -a

Volumes

List volumes

docker volume ls

Create a volume

docker volume create VOLUME_NAME

Delete a volume

docker volume rm VOLUME_NAME