Docker Commands 1

Docker Commands
run - list - stop - delete(rm) - delete and remove image (rmi) - pull

Note: Public Docker registry - dockerhub on the internet

Docker run command...
=====================
 RUN:  - used to run a container
      - will run from local repo, if not it will go to docker hub and pull the image
      onto your local disk drive.
    - If you do a docker run command and the image is not instructed to do anything,
       it will exit immediately, (first download if not on your local machine).
       > this example below will immediately will exit.
docker run unbuntu
  - However if you pass an argument then the image has something to do and will remain
    in operation. For instance:

docker run sleep 1000
 > (1k seconds) which is executing a command on the container.
  OR:

docker run -it centos bash
 > will open container and keep it open as in interactive terminal is opened
 i.e.- Then you can run a bash command as in: cat /etc/*release*
       > which will show the os and version info.

docker run -d = RUN IN THE BACKGROUND, so you get back to your terminal.

Docker List Command
===================
ps: lists all running containers and some basic info about them,
      including the id and the random name assigned by docker "silly_sammet"

docker ps

ps -a: list all containers running or not. Will list all containers that have run and exited.

docker ps -a


docker pull
============
 - downloads the image only and stores it on the local system

docker pull <image-name> to only pull the image.


Docker Stop Command
===================
docker stop silly_sammet <name of container or container ID>
  - must provide the container ID or the random name
    Therefore:  must run docker ps - to get the name or id.
    then you delete it by passing the required parameter.
* verify accuracy of this stmt: stop with delete = docker rm command
     -Will stop and remove the image.

Docker Remove Container Command
===============================

rm  - will remove containers and reclaim disk space.

docker rm <name of container or container ID>
    - you do not need to use all the chars of the container id,
      you can use just the first few letters
      and you can use multiple container ids in the same command.

Docker image command
=====================

docker image - will list all images downloaded to local


Docker Remove Images Command
============================

docker rmi <name of image>  must be stopped first.

Cannot remove an image if it is still in the containers repo because the image
has a container dependent on this particular image.


Docker Exec Command
===================
exec - execute a command on a running container.
-i = interactive =s keep STDIN open even if not attached
-t = terminal = Allocate a pseudo-TTY

i.e.
docker run -d ubuntu sleep 00 (-d is run in the background)
docker ps (shows container infallable_curie running)

docker exec infallible_curie cat /etc/hosts  (can also use the container_id)
 - will show the etc/hosts output.