Docker

Notes for docker command.

Images

• List all images: $ docker images

• Pull image from docker repo: $ docker pull ubuntu:18.04

• Create and run a container of an image in an interactive way: $ docker run -it ubuntu:18.04

• Create a new image from a container’s changes: $ docker commit $CONTAINER_NAME [REPOSITORY[:TAG]]

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Containers

• List all containers: $ docker ps -a

• Remove a container: $ docker rm $CONTAINER_NAME

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Docker hub

• Push image to repo: $ docker push <hub-user>/<repo-name>:<tag>

Host and Container

• Copy from container to host: $ docker cp <containerId>:/file/path/within/container /host/path/target

• Copy from host to container: $ docker cp /host/path/target <containerId>:/file/path/within/container

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Commit

$ docker commit -m $message$ <containerId> <repo-name>:<tag>

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CLI reference

Reference

$ docker run [OPTIONS] IMAGE [COMMAND] [ARG...]

• --detach, -d: Run container in background and print container ID

• --env, -: Set environment variables

• --interactive, -i: Keep STDIN open even if not attached

• --name: Assign a name to the container

• --net, --network: Connect a container to a network

• --rm: Automatically remove the container when it exits

• --tty, -t: Allocate a pseudo-TTy

• --volume, -v: Bind mount a volume

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Errors

• Unable to remove repository reference

Error response from daemon: conflict: unable to remove repository reference "$TAG/$NAME" (must force) - container 0bd2b54678c7 is using its referenced image 54bb4e8718e8

Error: failed to remove images: [$TAG/$NAME]

• Solution

$ docker ps -a # Lists containers (and tells you which images they are spun from)

$ docker images # Lists images

$ docker rm <container_id> # Removes a container

$ docker rmi <image_id> # Removes an image

# Will fail if there is a running instance of that image i.e. container

$ docker rmi -f <image_id> # Forces removal of image even if it is referenced in multiple repositories,

# i.e. same image id given multiple names/tags

# Will still fail if there is a docker container referencing image

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References

commit