Frequently Used Docker Image/Containter Commands

This post list commonly used docker commands.

Docker image

Docker image is the nucleus for container.

A simple text file that defines how an image should be built.

Execute additional process inside an already-running container
- docker container exec -i -t image-name /bin/sh
Run a container interactively
- docker run -it *image-name* sh
Run a container in detached mode
- docker run -d -P --name static-site prakhar1989/static-site
- -d will detach the terminal from the container. -P publish all exposed ports.-p localport:remote port can customize the port forwarding. --name is the name we give to the container
- docker port container-name will list all the published ports
Stop a detached container
- docker stop container-name
Automatically remove container when it exits
- docker run -rm *image-name*
Remove all containers that have exited
- docker rm $(docker ps -q -f status=exited)
- docker container prune
Manually create image from a container
- docker container commit sample my-image
See how custom docker image was built
- docker image history image-name

FROM: define which base image this image will be based on. On Docker Hub, there are a lot of officially curated images for various OS, development frameworks etc.
RUN: any valid linux command can follow RUN.
COPY & ADD: copy files or folders from host to the image. ADD keyword also lets us copy and unpack TAR files, as well as provide a URL as a source for the files and folders to copy.
WORKDIR: define the working directory or context that is used when a container is run from the image.
CMD & ENTRYPOINT: define what the start process is and how to start the process.