Docker 101

Docker [1] manages and runs containers, a thing that acts like an operating system. It is similar to a virtual machine, but a container uses a lot of the underlying operating system (called the "host") to work. Instead of building a whole operating system with emulated hardware, its own kernel, and so on and so forth, a container uses everything it can from the underlying machine, and, if it is well-designed, implements only the bare essentials to run the application or service you want it to run.

Whereas virtual machines are designed to run everything a regular machine can run, containers are usually designed to run very specific jobs. That is why Docker is so popular for online platforms: You can have a blogging system in one container, a user forum in another, a store in another, and the database engine they all use in the background in another. Every container is perfectly isolated from the others. Docker allows you to link them up and pass information between them. If one goes down, the rest continue working; when the time comes to migrate to a new host, you just have to copy over the containers.

But there's more: Docker is building a library of images [2] that lets you enjoy whole services just by downloading and running them. These libraries are provided by the Docker company or shared by users and go from the very, very general, like a WordPress container [3], to the very, very niche, like a container that provides the framework to run a Minetest [4] server [5].

[...]

Use Express-Checkout link below to read the full article (PDF).

Buy this article as PDF

Express-Checkout as PDF
Price $2.95
(incl. VAT)

Buy Linux Magazine

SINGLE ISSUES
 
SUBSCRIPTIONS
 
TABLET & SMARTPHONE APPS
Get it on Google Play

US / Canada

Get it on Google Play

UK / Australia

Related content

  • An open source, federated video sharing platform

    With PeerTube you can self-host your videos without the limitations embedded in YouTube and similar platforms.

  • Tutorials – Cordova Sensor

    Frameworks like Cordova make creating simple mobile apps quite easy. Making apps that use your phone's sensor is slightly trickier, but, thanks to a new universal standard, things are not as hard as you may think.

  • Docker Open Source Developer Tools

    Docker provides the open source tools and resources for compiling, building, and testing containerized applications.

  • Cordova

    Roll out an app elegantly and quickly for up to eight operating systems using the Cordova framework. According to the Apache Foundation, the only requirements are knowledge of HTML, CSS, and JavaScript.

  • Tube Archivist

    Tube Archivist indexes videos or entire channels from YouTube in order to download them with the help of the yt-dlp tool.

comments powered by Disqus
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters

Support Our Work

Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.

Learn More

News