Welcome to Yet Another Useless Blog
Despite the name, we hope you'll find these articles genuinely helpful! 😊
Who are we?
We're Thomas Jungbauer and Toni Schmidbauer — two seasoned IT professionals with over 20 years of experience each. Currently, we work as architects at Red Hat Austria, helping customers design and implement OpenShift and Ansible solutions.
What's this blog about?
Real-world problems, practical solutions. We document issues we've encountered in the field along with step-by-step guides to reproduce and resolve them. Our goal: save you hours of frustrating documentation searches and trial-and-error testing.
Feel free to send us an e-mail or open a GitHub issue.
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Step 3 - SonarQube
After the Pipeline has been created and tested we will add another Task to verify the source code and check for possible security issues, leveraging the tool SonarQube by Sonar.
Step 4 - Verify Git Commit
Besides checking the source code quality, we should also verify if the commit into Git was done by someone/something we trust. It is a good practice to sign all commits to Git. You need to prepare your Git account and create trusted certificates.
Step 5 - Build and Sign Image
Finally, after pulling and checking the code, we are going to create the image. During this process the image will be signed and uploaded to the public registry Quay.io.
Step 6 - Scanning with ACS
In this step we will install Advanced Cluster Security (ACS) and create 2 new steps in our Pipeline to scan the image for vulnerabilities and security policy. A custom security policy, configured in ACS, will verify if the image is signed.
Step 7 - Generating a SBOM
A software bill of materials (SBOM) offers an insight into the makeup of an application developed using third-party commercial tools and open-source software. It is a machine-readable, formally structured list of all components. This list is important to gain visibility into what risks might exist in a package and their potential impact. It allows to prioritize the risks and define a remediation path. The teams can use the SBOM to monitor all components that are used across an application.
We will create a Task that will generate a SBOM and uploads it into an SBOM repository.
Step 8 - Updating Kubernetes Manifests
With the finalization of the build process and the security checks during this phase, it is now time to update the Kubernetes manifests and provide the new tag for the created image. I have forked (and cleaned up) another repository that will store all yaml specifications that are required for OpenShift. You can find this repository at: Kubernetes Manifests
Step 9 - Linting Kubernetes Manifests
At this point we have checked our source code, verified that it has been signed and has no vulnerabilities, generated a SBOM and updated the Kubernetes manifests, that are responsible to deploy our application on OpenShift. As everything with OpenShift these Kubernetes objects are simple yaml files. In this step we will perform a linting on these files, to verify if they follow certain rules and best practices.
Step 10 - The Example Application
If you read all articles up to here (congratulations) you know that we always update the README file of "The Application". But what is this application exactly and how can we update it like in a real-life example? The Globex UI application is built with Angular and was prepared for this journey. It is a quite complex application and requires Kafka to be installed as well. However, since I am not a developer and this tool was already available, I forked and re-used it. The original can be found at Globex UI
Step 11 - ACS Deployment Check
After the Pipeline prepared the new image for DEV it should be checked against ACS for policy compliance. This ensures that the deployment manifest adheres to policy requirements. The command line tool roxctl will be leveraged to perform this task.
Step 12 - Verify TLog Signature
Since the image has been deployed on DEV now, we need to prepare everything for production. Before we start, we need to confirm that the whole signing process has been passed and that our signature has been applied correctly. With CoSign we signed our image and used Rekor to create a transparency log. We will use this log to confirm that the image was signed.
Step 13 - Bring it to Production
If you reached this article, congratulations! You read through tons of pages to build up a Pipeline. The last two steps in our Pipeline are: Creating a new branch and creating a pull request, with the changes of the image tag that must be approved and will be merged then (We will not update the main branch directly!). Finally, we will do a "real" update to the application to see the actual changes.
Operator installation with Argo CD
GitOps for application deployment and cluster configuration is a must-have I am trying to convince every customer to follow from the very beginning when starting the Kubernetes journey. For me, as more on the infrastructure side of things, I am more focused on the configuration of an environment. Meaning, configuring a cluster, installing an operator etc.
In this article, I would like to share how I deal with cluster configuration when certain Kubernetes objects are dependent on each other and how to use Kubernetes but also Argo CD features to resolve these dependencies.
SSL Certificate Management for OpenShift on AWS
Finally, after a long time on my backlog, I had some time to look into the Cert-Manager Operator and use this Operator to automatically issue new SSL certificates. This article shall show step-by-step how to create a certificate request and use this certificate for a Route and access a service via your Browser. I will focus on the technical part, using a given domain on AWS Route53.
Using ServerSideApply with ArgoCD
„If it is not in GitOps, it does not exist“ - However, managing objects partially only by Gitops was always an issue, since ArgoCD would like to manage the whole object. For example, when you tried to work with node labels and would like to manage them via Gitops, you would need to put the whole node object into ArgoCD. This is impractical since the node object is very complex and typically managed by the cluster. There were 3rd party solutions (like the patch operator), that helped with this issue.
However, with the Kubernetes feature Server-Side Apply this problem is solved. Read further to see a working example of this feature.
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