July 24, 2017

You know Docker. But do you know all of the other container platforms out there? Here’s the long list of container frameworks worth knowing about today, from LXC and OpenVZ to rkt.

To many people, Docker is virtually synonymous with containers. That’s because Docker’s release in 2013 put containerization technology on most people’s radars for the first time.

Yet Docker didn’t invent containers—not by a long shot. Several other container frameworks existed before Docker came along.

In addition, since Docker’s debut in 2013, other container frameworks have been released.

List of Container Platforms

Following is a full list of container platforms that are relevant today:

  • FreeBSD jails: Long before most folks in the Linux world were thinking about containers, FreeBSD developers introduced jails in the early 2000s. Jails provide a software-defined environment where users and processes are isolated from the rest of the system. No one ever called jails containers, but jails essentially let you build something similar to an application container.
  • Solaris Zones: A solution for running guest operating systems on Solaris in a way that resembles containers.
  • OpenVZ: A containerization frameworks that runs on Linux. Released in the mid-2000s, OpenVZ was designed primarily for the purpose of running guest operating systems inside containerized environments, rather than containerizing just an application.
  • LXC: The container platform that came closest to making containers a big deal—but did not quite go that far—prior to Docker’s release. LXC appeared in 2008 as another containerization solution for Linux. Unlike OpenVZ and like Docker, LXC is oriented chiefly toward application-container workloads, rather than system containers. LXC originally provided the basis for Docker, but that changed early in Docker’s history.
  • Docker: The container platform that needs no introduction. Docker is an application container platform that now runs natively on Linux as well as Windows.
  • Rkt: A framework from CoreOS for creating application containers. The first stable release of Rkt appeared in early 2016. Rkt is compatible with the Docker ecosystem in most ways. It’s essentially an an alternative framework for creating and powering containers that lets you use the same management tools as you would with Docker.
  • LXD: While most people were focusing on Docker application containers, Canonical was busy readying LXD for production. LXD is a system container platform built on top of LXC. Like OpenVZ, it lets you run guest operating systems on a Linux host. Unlike OpenVZ, it has (arguably) more modern and mature tooling—and the backing of a major open-source software vendor.

Did I miss your favorite container framework? Please let me know.

Christopher Tozzi

Christopher Tozzi has covered technology and business news for nearly a decade, specializing in open source, containers, big data, networking and security. He is currently Senior Editor and DevOps Analyst with Fixate.io and Sweetcode.io.