Tagged: devops

Let's assume you're spinning up pure docker containers in your Kubernetes cluster. Not pods, but docker containers. For example you're using docker.inside in your Jenkins builds, and your Kubernetes is hosting the Jenkins instance. You'll notice that your docker container can't access services in your cluster.

Testing a website for accessibility might prove challenging. Fortunately with the advent of some opensource tools, it's easier to test for problems, but automating this is a challenge. In this article we'll explore how to setup a Jenkins pipeline that runs pa11y - a popular opensource accessibility checker - inside a docker container.

After the fiasco with the previous graphic card, I ordered a new one. Since Linux is Linux, nouveau was picked as the driver instead of the nvidia-drm. Because now we have a race condition: we just need to make sure that nouveau is never loaded first though.

When having multiple machines it makes sense to have them all using the same time. Otherwise it's pretty hard to track what happened where, especially when looking at logs. This is managed using the Network Time Protocol (ntp), and there's a package for that named ntp.

If you want to try Kubernetes locally you're in for a lot of trouble. Installing it requires you to deal with changing apt repos, installing docker, installing kubectl and kubeadm, provisioning, installing networking, configuring the keys for cluster access, etc. Fortunately Ubuntu offers an easier way, via snaps.

If we want to post process images, one way to have basic post processing, is to just process the SVG file with XSLT. This is possible, since SVG images are just simple XML files. Let's achieve that.

As we enter 2019, I am using clouds a lot - the Germanium infrastructure is on Kubernetes, my last project was on AWS, I stopped using Java in my personal projects, and started learning Cobol for work. Here's why.

Kubernetes provides ConfigMap objects that allow storing key value pairs into its own etcd storage. The backup of Kubernetes also includes then those objects. Mounting a single key from the config as a file in a container is also straightforward. We'll see in this article exactly how.

If you're trying to install a Kubernetes on bare metal, it's useful to document this experience in an Ansible playbook. This makes the installation of new clusters trivial. But after finishing the installation, on a reboot of the node, you might find out your cluster is not coming up. One possible reason is having the swap still enabled.

At its core, Ansible is a declarative system. You describe the state in which you expect your parts of the system to be in, and Ansible, via its modules, tries to get the system there. That's the reason why modules are idempotent. But how are we to approach simple shell executions?