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One of the hardest parts about Infrastructure As Code and  Configuration Management is establishing a discipline on developing, testing and deploying changes. Developers follow established practices and tools have been built and perfected over the last decade and a half. On the other hand sysadmins and ops people do not have the same tooling and culture because estensive automation has only become a trend recently. So if Infrastructure As Code allows you to version the infrastructure your code runs on, what good is it if then there are no tools or established practices to follow? Luckily the situation is changing and in this post I'm outlining a methodology for test driven development of SaltStack Formulas . The idea is that with a single command you can run your formula against a matrix of platforms (operating systems) and suites (or configurations). Each cell of the matrix will be tested and the result is a build failure or success much alike to what every half-decent de...

See all my Salt-related posts Welcome back! In our quest to simplify the configuration and automate our systems we have  installed  Salt on all our servers and then moved on to some  basic state management . We want of course to do more sophisticated stuff with salt and we'll get to that too. But first we want to make sure that all minions are aligned to the same salt version (the latest in this case). To do that we will add another state to our configuration which we will call (very much unimaginatively) salt.sls. The content is below: salt-minion: pkg: - latest service: - running - watch: - pkg: salt-minion This instructs minions to upgrade the salt-minion package on the node and, if upgraded, restart the service. To activate this state we'll edit the top.sls state file as follows: base: '*': - ntp - salt We are now ready to apply the changes. Let's start with a guinea-pig minion: [prompt]# salt 'expendab...

This post is the first in a series documenting the deployment of Salt on a small network ( ~ 100 hosts, initially targeting only linux-based ones which account for roughly half of it). Due to the low number of hosts I have gone for a single master layout. The linux hosts are for the greatest part running Centos 5.[4,5] in both x86 and x64 favors, and just a couple running SLES. Installing salt master The easiest way to install salt on Centos is to pull in the epel repository  : rpm -Uvh http://download.fedoraproject.org/pub/epel/5/i386/epel-release-5-4.noarch.rpm then install salt with yum: yum install -y salt-master Since minions by default will attempt to connect to the salt master by resolving an host named  salt  I configured a salt cname record for the salt master host in the dns server. At this point the master can be started with: /etc/init.d/salt-master start Note : I don't have firewall or SELinux enabled. In particular SE...

Now, I'm not a fan of Nagios and I always recommend OpenNMS over Nagios, but when a client is fixated with Nagios I take a deep breath and get work done with it too. Now it just happened that I couldn't convince a customer to use OpenNMS so I decided that if I really had to use Nagios I would do it in a way as innovative as possibile. The first phase in this kind of projects is usually gathering requirements, that is hosts/appliances to be monitored. So I opened up a Google Document spreadsheet and started typing. At a certain point it hit me, what if I could make this doc the source for all configuration and just be done with it? My spider sense were tingling and I knew I had just found a way to make a dull project an interesting and blog-worthy one. I created a spreadsheet like the one in the picture with only 4 columns: ip, name/description, location, groups. After that I shared the spreadsheet as csv and grabbed the url. From the shell I could now f...

Using expendable virtual machines for testing purposes is hardly a new concept. Now  pretty-please-with-sugar-on-top would be automating the whole create-provision-test-destroy cycle. Enter  Vagrant . Vagrant is a tool for building and distributing virtualized development environments. It allows automated creation, provisioning (with Puppet, Chef or shell scripts) and tear down. Installing Vagrant on Ubuntu 10.04 LTS (which I'm still running) requires the following: a 4.1.x VirtualBox distribution (the 3.1 bundled with Ubuntu will not work) a recent version of ruby (you guessed it: the 1.8.x bundled with Ubuntu will not work) To install VirtualBox add the following repo to /etc/apt/sources.list: deb http://download.virtualbox.org/virtualbox/debian lucid contrib non-free then issue the usual apt-get update and install with (remove stock packages first): sudo apt-get update sudo apt-get remove virtualbox-ose virtualbox-ose-dkms sudo apt-get install ...

In some cases it is practical in an application to have a single global settings file where all configuration is stored. Most often this configuration file varies between a deployment and another, depending on customer requirements, licensed features, backend technology, etc. When developing an application with Sproutcore 1.x (1.6 is assumed) it is not immediately clear how to do it, not because it is not possible but just because documentation on Abbot , SC's build tool is, to use an euphemism, well, scarce. So what do we want to do exactly? We want to have a single config.js file that is included before any other application file and, most importantly, must not be minified and packed so that on-the-fly editing or inspection is still conveniently possible. The file should be kept small anyway so that packing and minifying it is not going to be necessary. To do this we need to create a new .js file and place it wherever we like in the application tree. A sensible choice wou...