Using Docker containers to test Perl installations on multiple Linux versions
A Lifting Experience at the Dock
If you want to distribute your programs across multiple platforms, you need to prepare them to run in foreign environments from the start. Linux container technology and the resource-conserving Docker project let you test your own Perl modules on several Linux distributions in one fell swoop.
Virtualization as a panacea? No way! Instead of abstracting the complete hardware and operating system, the Docker project builds on support for Linux containers (LXC) [1] in newer Linux kernels and isolates environments at the process and filesystem level. Savings in terms of memory consumption and significant performance gains are good reasons for using containers instead of classical virtualization. Each server effortlessly running multiples of mutually isolated applications can open up completely new possibilities at the data center.
As in true virtualization, insulated containers decouple their components. For example, one big advantage: If two applications use the same library, but different versions, it is not an impediment, because each container automatically comes with everything it needs.
The Docker project [2] is based on the LXC features of newer Linux kernels and boots up a daemon that manages all Docker containers [3]. It runs on the host system and on VMs. In other words, if you have an older system that does not yet have Docker support in the kernel, you can simply produce, say, an Ubuntu 13 image with Vagrant [4] and install Docker on it [5].
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
US / Canada
UK / Australia