Tag Archives: Fedora Tools

How to (be a) man on Atomic Host

One major thing missing on the Atomic Host are manual pages. Not a terrible thing - you can always google for them, right? But what if you cannot? Then there is the Fedora Tools Docker image. Try this:

-bash-4.3$ alias man="sudo atomic run vpavlin/fedora-tools man"
-bash-4.3$ man systemd

You should see a manual page for systemd. Thinking about it, that's it. Nothing more you need to now about it. Simple:)

 

Running git on Atomic Host with Fedora Tools image

I added the Fedora Tools image to Fedora-Dockerfiles repository, as you might know from my earlier post. I'd like to introduce you to one use case for this image - git.

When I started to work more on Docker images, I started using Atomic Host(s) for testing as they boot faster and are easier to set up than classic installations. Problem was to get data in those VMs running Atomic Host as git was not present. That's where I first really appreciated the tools image.

bash-4.3# yum
bash: yum: command not found
bash-4.3# git
bash: git: command not found
bash-4.3# atomic run fedora/tools
[root@localhost /]# cd /host/home/vagrant/
[root@localhost vagrant]# git clone https://github.com/fedora-cloud/Fedora-Dockerfiles
Cloning into 'Fedora-Dockerfiles'...
remote: Counting objects: 2189, done.
remote: Compressing objects: 100% (9/9), done.
remote: Total 2189 (delta 3), reused 0 (delta 0), pack-reused 2180
Receiving objects: 100% (2189/2189), 915.13 KiB | 901.00 KiB/s, done.
Resolving deltas: 100% (1014/1014), done.
Checking connectivity... done.
[root@localhost vagrant]# exit
bash-4.3# ls
Fedora-Dockerfiles sync

It's simple, right? You can see there is neither yum/dnf, nor git on the host, but still, I was able to clone the repository from Github very easily. The important thing to notice is the path I cd'ed to: /host/home/vagrant. You can see /host prefix there. That's where the host's filesystem is mounted and where I can access it and modify it.

You can review the docker run command for the tools image f.e. with this command:

bash-4.3# docker inspect --format='{{.Config.Labels.RUN}}' vpavlin/fedora-tools
docker run -it --name NAME --privileged --ipc=host --net=host --pid=host -e HOST=/host -e NAME=NAME -e IMAGE=IMAGE -v /run:/run -v /var/log:/var/log -v /etc/localtime:/etc/localtime -v /:/host IMAGE

Obviously, you can do more, not just clone the repo - you can run commit, push, checkout or anything else the same way.

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;-)