Get started with Docker

Install Docker

Docker is available on multiple platforms. Check the following link to choose the best installation path for you:

If the above does not fulfil your requirements follow the link here .

Create & Execute the Dockerfile

Docker automatically build images by reading the instructions you provide in the Dockerfile. A Dockerfile is a text document that contains all the command a user could call on the command line to assemble an image.

The Dockerfile must start with the FROM instruction. Below is an example of a Dockerfile

# base image
FROM ubuntu:latest

# clean and update sources
RUN apt-get clean && apt-get update

# install basic apps
RUN apt-get install -qy nano

# install Python and modules
RUN apt-get install -qy python3
RUN apt-get install -qy python3-psycopg2

Follow this link to know more about creating a Dockerfile.

  • To login into your account

    $ docker login
  • Executing the Dockerfile commands

    To directly execute the file command use:
    $ docker build . (With this command <none> repo is created. To avoid this use the next command)
    Sending build context to Docker daemon 5.51 MB
    You can specify the name of the repository with:
    $ docker build -t your_name .

View all the Images

  • To view all the top level images run

    $ docker images
    The output:
    REPOSITORY   TAG      IMAGE ID       CREATED          SIZE
    your_name    latest   d6e415a70abf   8 seconds ago    210MB
    ubuntu       latest   747cb2d60bbe   2 weeks ago      122MB

    The above output states that the repository ubuntu is the base image, because of the FROM ubuntu:latest command in the Dockerfile.

    The your_name image is the combination of all the packages mentioned in the Dockerfile.

  • To delete the images

    $ docker rmi image_id


Docker containers ensures that the software will behave the same way, regardless of where it is deployed, because its runtime environment is ruthlessly consistent.

  • To create a container in your image use

    $ docker run -ti image_name
    Where :
            -       t : gives us the terminal
            -       I : allows us to interact with the terminal
    Output - root : root@contaner_id:/#
  • To exit from the container

    root : root@contaner_id:/# exit
  • To Check all containers in your image

    To list all the containers:
    $ docker ps -a
    To check the running container:
    $ docker ps
  • To delete the container

    $ docker rm contaner_id

Image to Docker Cloud

  • Search command to find suitable image

    $ docker search image_name

    Below is a screenshot for : docker search ubuntu
  • To pull the image

    $ docker pull username/repo_name:tag_Name
  • To commit the image

    $ docker tag IMAGE_ID username/repo_name:tag_Name
  • To push the image

    $ docker push username/repo_name:tag_Name