docker cheatsheet 🐳

intro

docker --version

docker engine version
docker version

docker version in detail
docker events

get real time events from the server
when a container stops, an image is pushed, daemon reloads etc
docker system df

shows docker disk usage

quick start from hub.docker.com

git clone https://github.com/docker/doodle.git
cd doodle\cheers2019
docker build -t erencelik/cheers2019 .
docker run -it --rm erencelik/cheers2019
docker login
docker push erencelik/cheers2019

gets the repo, builds an image from the Dockerfile
runs it as a container and pushes the image to your registry in hub.docker.com

images

docker images

lists all images
docker tag erencelik/dummy-project:1.0.0.RELEASE erencelik/dummy-project:latest

tags an image
docker tag SOURCE_IMAGE[:TAG] TARGET_IMAGE[:TAG]
docker pull ubuntu

downloads the image
if no tag specified, downloads 'latest' as default
docker image rm <iid>

removes image locally
first 2-3 chars of image id is enough as long as it's unique in local
if you get the error:
unable to delete - image has dependent child images
try using repository name and tag instead of image id:
docker image rm ubuntu:latest
docker search ubuntu

searches images from docker hub and lists
docker image history <iid>

shows the history of an image
docker image inspect <iid>

shows detailed information of an image
docker build .

builds an image from a Dockerfile in current directory
an url or path can be given
docker push dummy-project:latest

push an image or a repository to a registry

containers

docker container ls

shows the running containers
docker container ls -a

shows all containers
docker ps

shows the running containers
docker ps -a

shows all containers
docker container run hello-world or docker run hello-world

runs a container
if not available locally, downloads
docker run -p 1903:8080 erencelik/dummy-project

publishes exposed port(8080) of project to host(1903)
host-port:container-port
docker run -p 1903:8080 -d erencelik/dummy-project

runs in detached mode (background)
docker run -it ubuntu

i for interactive and t for tty
it runs the container and takes you straight inside the container
here it creates an interactive bash shell in ubuntu
'exit' command will exit shell
docker run -dit ubuntu

we do the same but in detached mode
it creates shell but we don't directly go there
docker exec -it <cid> sh
with this command we can go shell after running in detached mode
docker run -tid --name my-ubuntu ubuntu

assigns a name to the container
docker run -it --rm erencelik/cheers2019

--rm automatically removes the container when it exits
docker container stop <cid>

stops a running container
docker container pause <cid>
docker container unpause <cid>
docker container inspect <cid>
docker container prune

removes all stopped containers
docker container kill <cid>

immediate stop
docker run -p 8080:8080 --restart=always erencelik/dummy-project

when you restart docker desktop, the container restarts too.
restart=always or restart=no. default is no.
docker top <cid>

displays the running processes of container
docker stats

shows all the stats about the running containers
docker run -p 8080:8080 -m 512m erencelik/dummy-project

specific max memory: 512m/1g
docker logs <cid>

shows the logs of a container
docker logs -f <cid>

follow logs
docker cp

copies files/folders between a container and the local filesystem
docker cp CONTAINER:SRC_PATH DEST_PATH
docker commit my-ubuntu erencelik/dummy-project:0.0.2

creates a new image from a container’s changes
this command allows us to take a running container and save its current state as an image
for example you can run some commands in a running container via exec, make some changes
and immediately create a new image with the latest situation
takes two parameters: docker commit CONTAINER REPOSITORY[:TAG]

task:

run a container from ubuntu image with a specific name
install nginx in this container
view nginx welcome page and exit