Container Virtualization Comeback with Docker

Container Terminal

Conclusions

Docker extends LXC, adding a number of useful features that make the software more attractive. The developers of the solution have largely oriented Docker with the requirement of being able to distribute applications in the Docker container format quickly and easily and so that they are capable of running on any system.

However, in reality, Docker will tend to be especially interesting for those setups in which virtualization is desired, but without the overhead of a fully virtualized system.

Docker offers an attractive middle ground here, and it's indeed no coincidence that the software has many fans and is experiencing some hype. Especially in combination with a lean OpenStack setup, Docker could develop into a really useful tool for many tasks. It already comes with many practical tools in its own right.

A working setup, however, relies on the Docker driver for OpenStack Nova, and this should not be based on software from the Iron Age. If you want to run Docker without tying into frameworks such as OpenStack, you will find that it is already a reliable tool today.

Docker is reliable primarily because the Docker API is very versatile, supporting, for example, seamless integration with automation tools like Puppet and Chef, in addition to the features mentioned earlier. Overall, Docker has what it takes to become an admin's darling and is definitely worth a closer look.

Infos

Docker documentation: http://docs.docker.io/en/latest/
DockerUI: https://github.com/crosbymichael/dockerui
Shipyard: https://github.com/shipyard
OpenStack Nova: http://nova.openstack.org/
Bug report for Docker in Nova: https://bugs.launchpad.net/nova/+bug/1247295

The Author

Martin Gerhard Loschwitz works as a Principal Consultant at hastexo. His work focuses on high-availability solutions, and in his spare time he maintains the Linux Cluster Stack for Debian GNU/Linux.