What is Docker Engine?
In short Docker engine is the core part of Docker which creates and executes docker containers. There are some top orchestration tools provided by multiple vendors including Docker’s built-in orchestration. We will cover Orchestration in another article but for now lets concentrate on docker engine.
So If docker engine creates and executes docker containers then what is a docker container?
Docker Container
In short a docker container is an instance of docker image which can be an OS specific image with some configuration in it. These docker images are used to run specific services. For example you don’t want to install Nginx or Node.js services in your local machine and rather run them in some VM (virtual machine) for isolation. The issue with the VM is that it has an overhead of resources consumption, where as docker keeps your services isolated with lowest overhead.
Installing Docker Engine
Make sure you have sudo rights. This article assumes that you want to run docker as a normal user which is safe and good.
Docker Engine Installation in Debian Jessie
- Installing apt utilities and Docker Official GPG key
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sudo apt-get install apt-transport-https ca-certificates curl gnupg2 software-properties-common curl -fsSL https://download.docker.com/linux/debian/gpg | sudo apt-key add - |
- Adding repository (AMD64 for 64 bit processors)
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sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/debian $(lsb_release -cs) stable" |
- Running apt-get update
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sudo apt-get update |
- Install Docker engine community Edition
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sudo apt-get install docker-ce |
- Adding user to docker group
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sudo usermod -aG docker whoami |
- Reboot or Log off
Testing Docker
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$ docker run hello-world |
and here is the output.
Unable to find image ‘hello-world:latest’ locally latest: Pulling from library/hello-world 78445dd45222: Pull complete Digest: sha256:c5515758d4c5e1e838e9cd307f6c6a0d620b5e07e6f927b07d05f6d12a1ac8d7 Status: Downloaded newer image for hello-world:latestHello from Docker! This message shows that your installation appears to be working correctly. To generate this message, Docker took the following steps: To try something more ambitious, you can run an Ubuntu container with: Share images, automate workflows, and more with a free Docker ID: For more examples and ideas, visit: |