raynix 筆記

Tag: kubernetes

  • Fixed: Duplicated Cluster IPs in a Kubernetes Cluster

    A Cluster IP is an IP address allocated in the cluster’s virtual LAN, usually allocated to Kubernetes Services. As a user nobody should care about which cluster IP a service would get because we will use the service-name.namespace-name DNS name which will map to that IP automatically. In my case, some services in a GKE…

  • The Upgrade of Kubernetes Ingress Nginx

    The ingress-nginx container image I’ve been using was v0.25, and that’s more than 1 year old. The recent release is v0.44 but it’s a big leap from 25 to 44 and I’ve found some major differences between the 2 versions. Version 0.25 implemented API version of networking.k8s.io/v1beta1 while version 0.44 has networking.k8s.io/v1. Here are samples…

  • Kubernetes: How to Use Affinity

    Affinity is a great feature in Kubernetes to assign pods to nodes based on labels. In my case, I have a hybrid Kubernetes cluster with half nodes are of X86 architecture and other half of ARM architecture, and I need to deploy the X86 only containers to the X86 nodes. Of course I can build…

  • Kubernetes and GitOps with Flux CD V2.0

    GitOps could be the next big thing in cloud automation so I’d give it a try with my in house hybrid Kubernetes cluster. I was recommended to try Flux CD and there’s a good reference project initiated by my colleage: k8s-gitops. However, in order to fully understand how to use Flux CD, I chose to…

  • Hybrid Kubernetes Cluster (X86 + ARM)

    The one in the picture was my old laptop, then my daughter’s for a few years. Now she got a nice new 2-in-1 ultra book the school asked us parents to buy, this clunky one was gathering dust on shelves. I tried to sell it but got no one’s attention despite it has got i7…

  • Renew Certificates Used in Kubeadm Kubernetes Cluster

    It’s been more than a year since I built my Kubernetes cluster with some Raspberry PIs. There was a few times that I need to power down everything to let electricians do their work and the cluster came back online and seemed to be Ok afterwards, given that I didn’t shutdown the PIs properly at…

  • Use Variables in Kustomize

    Variables in Kustomize are handy helpers from time to time, with these variables I can link some settings together which should share the same value all the time. Without variable I probably need to use some template engine like Jinja2 to do the same trick. Some examples here. In my case, there’s a bug in…

  • Using Sealed Secrets in a Raspberry Pi Kubernetes Cluster

    Sealed Secrets is a bitnami Kubernetes operator aimed to one-way encrypt secrets into sealed secrets so that they can be safely checked-in into GitHub or other VCS. It’s rather easy to install and use Sealed Secrets in a Kubernetes cluster on AMD64 architecture, but not so on my Raspberry Pi cluster. First, the container image…