Category: Kubernetes, CKA, ReplicaSet, Labels, Selectors Introduction One of the biggest improvements of ReplicaSet over the old ReplicationController is its more expressive label selectors. ReplicationController supports only simple equality-based selectors such as: ReplicaSet introduces set-based selectors, allowing you to create much more flexible selection rules using matchExpressions. In this hands-on lab, we’ll explore all four ReplicaSet selector operators: We’ll also verify each operator by changing Pod labels and observing ReplicaSet’s

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In this blog, I will demonstrate: What is ReplicationController? A ReplicationController (RC) ensures that a specified number of Pod replicas are always running. If a Pod crashes or is deleted accidentally, Kubernetes automatically creates another Pod. Responsibilities Lab-1: Create a Single Pod Create an nginx Pod. Output Check the Pod. Output Delete the Pod Output Check again. Output Notice that Kubernetes does not recreate the Pod because it is an

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A Kubernetes cluster consists of two main components: The recommended upgrade order is: In this tutorial, we will upgrade a Kubernetes cluster from v1.35.1 to v1.35.2 using kubeadm. Kubernetes Cluster Architecture Prerequisites Before starting the upgrade, ensure that: Current Cluster Version Example Output Part 1 — Upgrading the Control Plane The Control Plane manages the Kubernetes cluster. It is responsible for scheduling Pods, maintaining cluster state, handling API requests, and

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🌐 Introduction Kubernetes is the most popular container orchestration platform used by companies worldwide. As a CKA (Certified Kubernetes Administrator) candidate, one of the most important skills is building a Kubernetes cluster from scratch. In this lab, we will: ✅ Create a Kubernetes Cluster using Kubeadm✅ Install Containerd Runtime✅ Configure Kernel Modules✅ Install Kubernetes Components✅ Deploy Calico Network Plugin✅ Join Worker Nodes✅ Verify Cluster Health ☁️ Step 1: Create a

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