Docker basics

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Docker basics

Run a docker image

To run a docker image use

    docker run hello-world

Docker first searches for image locally. If it is not found then it will download the image from docker hub and run it.

See local docker images in cache

To see local docker images in cache use:

    docker images

Docker basics are learned from https://docs.docker.com/linux/started/

Download public docker images

Public docker images are available at https://hub.docker.com/ They can be downloaded using:

docker pull centos

Then the same image can be used using:

docker run -it centos bash

Most images have documentation explaining their purpose and how to use them.

Listing currently running docker containers

To list currently running docker containers use:

docker ps

Read "man docker" for more information on docker command

Instead if you want to list stopped/killed containers use:

docker ps --all

Deleting a docker container

To delete a docker container, first list the containers using:

docker ps --all

Then delete the desired container using:

docker rm <container-name>

To delete all docker containers on the system use:

docker ps --all | wc -l
docker rm $(docker ps --all | tail -<count> | cut -b1-12)

where count is one less than number reported in wc -l to exclude the top title row.

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