Tag Archives: Containers

Containers: Resurrection vs. Reincarnation

This post is to share that I am coining new analogy about containers, cloud and orchestration. Everyone uses Pet vs. Cattle, some use Ant. vs. Elephant. These animal analogies are fine and describe how YOU behave to your machines/containers if something bad happens.

But it's also important to look at things from the other side - what actually happens to the app? How does it feel? How does it perceive world around itself?

Resurrection

In a good old Mode1 world things were simple. Some app died, so you went and resurrected it back to life. Sure, PID was different, but it was the same machine, same environment, same processes around it. Feels like home...

Reincarnation

Then the cloud and container world appeared and people realised they don't want to bring dead things back to life (it might have something to do with all the scary zombie movies, I think). And so in container orchestration you just get rid of things that appear to be dead and then bring new ones to life. And you app is reincarnated instead of resurrected

Resurrection vs. Reincarnation.

Reincarnation is not completely new in IT world - it was already used in MINIX many years ago:). But I am coining this new analogy for containers context. Obviously, it's up to you now to share the wisdom and make sure people know who was the original prophet!

Forget resurrection, reincarnation is a way to go!

 

Fedora Tools Docker image

I got this request from my colleagues if there is something like Red Hat Atomic Enterprise Tools container image available for Fedora or CentOS. The answers was no, there isn't, thus I started to work on it. I'd like to tell you what it is and why do I invest my time into it.

First of all, Fedora Tools image is meant to be used mostly on Atomic Host as there is no way to install missing tools with yum or dnf. We could create tons of small images each containing a single tool. But that would a) make it hard for users to find all the tools, b) consume more space then a single image if you decide to use many (all...) of them, c) be hard to maintain.

These 3 reasons lead us to create a single image containing big number of tools important to sysadmins, performance analysts, or just users that need man pages on Atomic Host. This image is pretty big (more than 1 GB), but can be pretty useful.

Current version of the Dockerfile can be found in Fedora-Dockerfiles repository. You can find the list of additional packages (to what's already in a base image) starting on line 13.

The basic information on how to use the Fedora Tools Docker image can be found in README file and I hope to provide more how-to's here soon:).

I've set up an automated build as vpavlin/fedora-tools under my namespace on Docker Hub. To try the image, you can do:

atomic run vpavlin/fedora-tools

Enjoy;-)