Sometimes, it gets essential to prompt the user to confirm if the user is okay with the operations of the playbook. For example, if a playbook is going to perform an action that would cause a service impact, I would probably want to inform the user about the consequences and let him choose to abort […]
This post will show a simple tool to create a Kubernetes cluster using libvert and kubespray. Libvert needs to know the introduction; if you are working on a Linux environment, you are likely a fan of libvert already. I have written a set of playbooks to leverage libvert to spawn a cluster of virtual machines,
Create Kubernetes cluster locally using Kubespray and libvert Read More »
In this post, we will see some advanced options provided by kubespray for production-grade cluster creation. In most places on the internet, you will see the basic instructions to create a simple(Hello World) Kubernetes cluster using a bunch of virtual machines. However, kubespray offer much more than that. For example: 1. You can install several
Kubespray advanced configuration for a production cluster Read More »
This post demonstrates how load balancers help achieve higher availability of the control plane nodes in a simple cluster environment. The post targets the beginner audience; with the concepts, procedure, and testing. The same concepts apply to setting up a high-available Kubernetes cluster. The post is divided into three parts; feel free to skip to
What is high availability, and how to make your infrastructure resilient to failures? Read More »
In this post, we will see an automated approach to creating a guest VM with cloud-init using libvert/virt-install. In the Previous post described here, we have seen the manual procedure. Now, we will use a shell script wrapper to do the same for our convenience. For your convenience, the script is loaded with comments, so
Create a Virtual Machine with cloud-init using libvert(Automated) Read More »
This post will demonstrate creating a high-performance guest VM with cloud-init using virt-install. The Qemu/libvert/KVM stack is currently the best bet to get the near-native performance from the virtual machines. When combined with cloud-init, the stack gets more empowered and highly convenient to set up virtual machines. This is especially helpful if you require creating
Create Virtual Machines using virt-install(libvert) with cloud-init Read More »
In this post, we will see how to install longhorn into your Kubernetes cluster. If you are not familiar with longhorn block storage, it is a production-ready block storage solution specially designed for Kubernetes. you can install longhorn on any managed Kubernetes cluster, on-prem, or even in your home lab. It is a lightweight solution
How to setup longhorn block storage for Kubernetes cluster Read More »
In this post, we will see 4 methods to fetch the Kubernetes CA Certificate. This may be needed by the services to validate their certs by the Kubernetes CA. I would prefer the one from the last two methods described here, however, it depends on your use case. Eg: You need it outside of the
This post will show the steps to configure a simple mutation webhook in the Kubernetes cluster. If you are not familiar with webhooks, you can read about them HERE. For this post, I will be using a python(flask) based webserver as a webhook for simplicity. Objective/Example Usecase: In this post, we will set up a
This post describes how to write and configure a Kubernetes validation webhook in a Kubernetes cluster. The details about “what is a validation webhook” is described here. You can find the code used in this post on this GitHub page. Pre-requisites: You must have admin privileges in the cluster. Some knowledge of JSON. Some knowledge
How to setup a validation webhook in Kubernetes? Read More »
