Since we know now why to use Sensu, it is about time to get some real work done. Let’s install Sensu!

The very first point to stop for learning how to install Sensu is the installation guide in the Sensu Wiki.

I have summarized the installation steps in separate shell scripts for CentOS and Debian, and placed them in a repository on Github

Installation on CentOS #

For CentOS (CentOS-6.3-x86_64-minimal) I have logged into my box and executed the following:

curl https://raw.github.com/tobias-wissmueller/sensu-sandbox-shell/master/install_sensu_centos.sh | bash

This will perform the following steps:

{% gist 5264026 sensu_sandbox_centos.sh %}

Installation on Debian #

On a Debian 7.0 (Debian-7.0-b4-i386-netboot) box I ran the installation procedure with:

curl https://raw.github.com/tobias-wissmueller/sensu-sandbox-shell/master/install_sensu_debian.sh | bash

All in all, that’ll execute the following commands:

{% gist 5264026 sensu_sandbox_debian.sh %}

Test, Test, Test! #

A simple check if everything has been installed correctly is by pointing the browser to http://<your_machine>:8080/clients. It should display the Sensu dashboard with a connected client.

Glad it worked out!

First Shoot then Ask #

So, what is that all good for? The first time I did all those steps, I wondered about all that new software on my box that I have never heard of. Let’s do a quick introduction.

EPEL Repository #

Only required on CentOS though, the EPEL repository extends Enterprise Linux (Red Hat Enterprise Linux, CentOS, …) with additional software packages.

Erlang #

Erlang is a programming language for building robust fault-tolerant distributed applications.

RabbitMQ #

RabbitMQ is a middleware that serves as a message broker between systems. It has been written in Erlang.

Redis #

All that data needs to go somewhere, right? Redis will take care of it, since it provides a key-value based storage machanism.

Sensu Package Repository #

Since Sensu is not part (yet?!) of any offical package repository, the project provides it’s own, to make it as easy as possible to install all necessary components in an easy to handle omnibus-style package.

Sensu #

Doesn’t need much of an explanation here. Anyways, check out the new shiny website of Sensu. Also have blogged about why to use it.

Contribute to Sensu! #

If you need installation steps for another system please feel free and take the initiative to contribute to the Sensu WiKi. Extra bonus for summarizing your installation procedure into a script and contributing it to that repository.

What’s next? #

In the next two parts I will show two other and better ways how the installation can be done. Although, it is nice to put all installation steps into a script and be able to execute them with a one-liner, it is not the best way of managing software installations. There are smarter ways of how to do that. Good times we are living in!

Done for today!