Day 38: Admission Controllers in Kubernetes | Mutating & Validating | CKA Course 2025
Day 38: Admission Controllers in Kubernetes | Mutating & Validating | CKA Course 2025
👉 GitHub Repository: https://github.com/CloudWithVarJosh/C...
👉 CKA 2025 Playlist: • CKA Certification Course 2025
📚 Welcome to Day 38!
Today we explore one of the most powerful layers of control in the Kubernetes API lifecycle: Admission Controllers. These plugins let you mutate or validate API requests before they are persisted to etcd — giving you fine-grained control over what gets admitted into your cluster.
📝 What We’ll Cover:
✅ What are Admission Controllers and how they work
✅ Difference between Mutating and Validating types
✅ How to list, enable, and disable admission plugins in kube-apiserver
✅ Understanding custom webhooks: architecture, use cases, and caveats
✅ Sequence of execution for admission plugins
✅ Security considerations in multi-tenant clusters
💡 By the end of this lecture:
You’ll be confident in identifying when and how admission controllers are triggered, how they enforce security and policy, and how to evaluate the right tooling (built-in vs webhook-based) for your Kubernetes use case.
🔗 Stay Connected:
👉 LinkedIn: / varun-joshi-2b516752
👉 GitHub: https://github.com/CloudWithVarJosh
💬 Got questions? Drop them in the comments — I’ll reply ASAP!
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⏰ Timestamps:
00:00:00 – Introduction
00:00:36 – What Is Admission Control in Kubernetes?
00:24:22 – Built-In vs Custom Admission Controllers
00:29:39 – Hands-On Demo: Enabling and Disabling Admission Plugins
00:36:25 – Webhook Authorization vs Webhook Admission
00:45:26 – Real-World Usage: How Enterprises Configure Admission Controllers
00:46:37 – Execution Order of Mutating and Validating Controllers
00:52:16 – Outro & Next Steps
🔖 Hashtags:
#Kubernetes #CKA #CloudWithVarJosh #CKACourse #CKA2025 #CKAExam #AdmissionControllers #KubernetesSecurity #MutatingAdmissionWebhook #ValidatingAdmissionWebhook #OPA #Gatekeeper #Kyverno #KubernetesTraining #K8sAPI #ClusterSecurity #DevOps #WebhookAuthorization #SecureKubernetes