Saving a Docker image:

docker save blitz | gzip > blitz-docker.tar.gz

Loading a Docker image:

gzcat blitz-docker.tar.gz | docker load
docker load -i blitz-docker.tar.gz
docker load < blitz-docker.tar.gz

Running the image:

docker run -it blitz

Building the image using the Dockerfile:

docker build -t blitz .

Removing all containers:

docker rm $(docker ps -a -q)

Removing the image 'blitz':

docker rmi blitz

Removing all images:

docker rmi $(docker images -q)


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Here are some of the commands that you may find useful.

To re-enter the docker container after you type "exit" at the command line inside the container, first obtain the container ID by using the "docker ps -a" command:

$ docker ps -a
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS                     PORTS               NAMES
a27382779765        blitz               "/bin/bash"         19 minutes ago      Exited (0) 5 seconds ago                       nifty_spence

Then use the docker start and the docker exec command to run it again:

$ docker start a27382779765
a27382779765

$ docker exec -it a27382779765 /bin/bash
root@a27382779765:~# 

You will see that changes you have previously made within that container have not been lost.

To switch to the next lab, it is a good idea to first remove all the containers and their images related to the previous labs:

To remove all the containers:

$ docker rm $(docker ps -a -q)

To remove all the images:

docker rmi $(docker images -q)