We recently had to install a bunch of applications on a customer’s shiny new OpenShift 3.11 cluster. Among others also GitLab. Turned out getting GitLab up and running on OpenShift is not so easy. What I found on the Internet about installing GitLab on OpenShift was partly outdated and not 100% accurate. Most information was about getting GitLab into a Kubernetes cluster. So I had to adapt these information to the situation in an OpenShift cluster.
This article is the conclusion of all these findings and efforts and gives a step-by-step recipe on how to install GitLab on OpenShift.
Recently, I stumbled on a situation where I wanted to add a couple of values to an OpenShift deployment configuration. Previously I had modified or added a single attribute in a yaml file with
oc patch. So I started to wonder whether it is possible to update multiple attributes with
oc patch as well. To get right to the result: Yes, it is possible. This article will show you which features
oc patch and likewise
kubectl patch really have, beside a simple modification of one attribute.
After some time, let’s move on to another topic around making OpenShift environments more developer friendly. This time we are going to look at what happens, when a system test actually failed, and how to enable developers to properly react.
Kubernetes and OpenShift have a lot in common. Actually OpenShift is more or less Kubernetes with some additions. But what exactly is the difference?
It’s not so easy to tell as both products are moving targets. The delta changes with every release - be it of Kubernetes or OpenShift. I tried to find out and stumbled across a few blog posts here and there. But they all where based on not so recent versions - thus not really up-to-date.
So I took the effort to compare the most recent versions of Kubernetes and OpenShift. At the time of writing v1.13 of Kubernetes and v3.11 of OpenShift. I plan to update this article as new versions become available.
The OpenShift command line interface is a very powerful tool which is quite useful for beginners and advanced user of OpenShift alike. Some of its features are not well documented or not documented at all. In this article I would like to shed some light on commands that I personally find useful and that are, from my observation, not widely in use. So without further ado, let’s start with the commands:
Our world is full of various processes: tracking of goods delivery, currencies trading, monitoring of server resources, hotel bookings, selling goods or services etc. Since these processes occur over time, they can be described by time series data.
Successful businesses always take advantage of their data by analyzing it and then making predictions (e.g. predicting volume of sales for the next month) and business decisions (e.g. if the volume of sales grows then additional goods need to delivered to a warehouse).
There are a number of technologies for analysing the time series data. This article gives an introduction to one of them which is called TimescaleDB which is an open source solution for time series data analysis based on battle-tested PostgreSQL DBMS.
Let’s move on with this little series about how OpenShift environments may fall short in terms of developer experience.
Today we focus on the role that system tests have in an OpenShift infrastructure and what might possibly go wrong here testdata-wise.
In some OpenShift environments for building and delivering software we notice that the needs of developers, arguably a group of people who will have a great deal of contact with the platform, are not met as thoroughly as would have been possible.
Especially when it comes to software testing there is often much room for improvement. The usage of container platforms can improve testing techniques a lot but might also be a major blocker when it comes to the provided infrastructure. Good testing is already hard. Everything that makes it even harder, by forcing your developers into workarounds or compromises on testing quality will result in larger round trips, more testing effort, less valid testing, in short: wasted time.
So in this mini series of blog posts we will have a look into some possible fields of improvement and give recommendations on how to fix the respective situation.
Today we evaluate the fact, that some CI/CD setups for OpenShift may spoil the most simple type of testing a developer uses: Just running the software locally - in OpenShift.
Docker Headless VNC Container 1.3.0 has been released today. The different Docker images contains a complete VNC based, headless UI environment for testautomation like Sakuli does or simply for web browsing and temporary work in a throw-away UI container. The functionality is pretty near to a VM based image, but can be started in seconds instead of minutes. Each Docker image has therefore installed the following components:
There are a lot of articles that show how to monitor an OpenShift cluster (including the monitoring of Nodes and the underlying hardware) with Prometheus running in the same OpenShift cluster. This article however is based on a different scenario: You are responsible for an application on an OpenShift cluster and want to monitor just this application, but you don’t have any administrative permission on it. The reason for this can be that you are working in a big company where the operation of the OpenShift environment is outsourced or the process to introduce a new monitoring solution takes way too long or the current monitoring solution doesn’t match your requirements and so on.
In this article I’m going to show you how to setup the monitoring of a demo application in 6 easy steps. The example is built in that manner that it will be easy for you to do the same for your application. A side note: If the OpenShift cluster that you are using will be monitored in the future with a different Prometheus setup, you don’t need to start from scratch. You might need to tweak the configuration of your scraping a bit and you need to move your dashboard to a different Grafana but that should be it.
Docker Headless VNC Container 1.2.0 has been released today. The different Docker images contains a complete VNC based, headless UI environment for testautomation like Sakuli does or simply for web browsing and temporary work in a throw-away UI container. The functionality is pretty near to a VM based image, but can be started in seconds instead of minutes. Each Docker image has therefore installed the following components:
The GitHub repository toschneck/openshift-example-bakery-ci-pipeline contains, the sourcecode for the examples of the talk Continuous Testing: Integration- und UI-Testing mit OpenShift-Build-Pipelines at the Redhat/ConSol OpenShift-Day:
Sowohl End-2-End-Testing als auch End-2-End-Monitoring folgen dem gleichen Paradigma – sie betrachten eine Applikation aus der Sicht des End-Users. Hier darf es keine Rolle spielen, in welcher Oberflächentechnologie die Applikation geschrieben ist oder in welcher Art sie mit dem End-User in Verbindung tritt. Genau an diesem Punkt setzt das Open-Source-Tool Sakuli an.