> For the complete documentation index, see [llms.txt](https://notes.tatusl.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://notes.tatusl.dev/kubernetes/admission-controller.md). # Admission Controllers * Admission controllers checks whether request to apiserver should be allowed or not (after authentication and authorization) * Dynamic admission controllers * can call validating service with webhook * this is beneficial for example in managed Kubernetes environments where API server can't be modified * configured with `ValidatingWebhookConfiguration` * Mutating admission controller can modify workloads, for example inject init containers * Kubernetes can send out `AdmissionReview` object to admission controller, which wraps the object which will be validated * Admission controller need then respond with the validation results to the apiserver ## Resources * TGI Kubernetes 119: Gatekeeper and OPA -