Posts

Prometheus labels every data point — the most well-known example of a label is (probably) instance. Take a look at this query result (query: up{job="prometheus"}): up{instance="127.0.0.1:9090",job="prometheus"} 1 So what does this tell me? I queried for the “up” metric and filtered it for “prometheus” — yay. The “1” says, my service is alive. So far so gut. Readability Since we are in the process of running a few Prometheus servers (in federation), each of those metrics will report back with instance="127....

We use Ansible for all kinds of things. One of it being formatting and mounting a volume to be able to use it. When I introduced the code for that, it worked (flawlessly, of course) — until I hit a bug when I provisioned another cluster. Long story short, I was able to fix the bug. But since we rely on it to work always, and I wanted to make sure I had all situations covered, I decided to extend one of our tests....

As I am spiralling into Linux server administration, there’s certainly a lot to learn. Certainly a lot leaves me wanting BSD, but since that’s not an option, … here we go. NetworkManager The NetworkManager on Linux (or CentOS specially) manages the network. Whatever content/blog posts/knowledge base I found. It usually suggests that you uninstall it first. Common problems are that people are unable to manage /etc/resolv.conf — because changes made by them to that file get overwritten again....

(Hello again. I haven’t blogged in a while. But since I’m growing weary of platforms such as medium. Here we go.) I’ve recently spent too much a lot of time with Ansible. Once I got into the rhythm of playbooks, roles and maybe modules/libraries, I desperately needed a way to test my YAML. And by testing, I didn’t mean the annoying linting that Ansible ships with, but actual (integration) tests to verify everything works....

I’m a huge advocate of CI and one service in particular called Travis-Ci. Travis-CI runs a continuous integration platform for both open source and commercial products. In a nutshell: Travis-CI listens for a commit to a Github repository and runs your test suite. Simple as that, no Jenkins required. At Imagine Easy we happily take advantage of both. :) So what’s wrong? For some reason, every other open source project (and probably a lot of closed source projects), use Travis-CI wrong in a way, that it will eventually break your builds....