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Hands-on Lab·Certified Kubernetes Administrator

RBAC Roles and Bindings

Four object kinds, one verb-and-resource model, and a command that answers permission questions without trial and error. Build a read-only ServiceAccount, prove it with auth can-i, then get a real 403 from inside a Pod using its own token.

Cluster Architecture and Configuration Guide 15 of 103 Intermediate

Written against the versions above. Rule contents are choices. The deny-by-default model and the additive-only evaluation are not.

Any cluster does. Everything below is `kubectl` against the four-node lab.
Server NameIP AddressOSRolesCPURAMHDD
CKA1001192.168.0.175Ubuntu 26.04 LTSControl Plane Node2 Core4 GB50 GB
CKA1001-NODE01192.168.0.176Ubuntu 26.04 LTSWorker Node2 Core4 GB50 GB
CKA1001-NODE02192.168.0.177Ubuntu 26.04 LTSWorker Node2 Core4 GB50 GB
CKA1001-NODE03192.168.0.178Ubuntu 26.04 LTSWorker Node2 Core4 GB50 GB

Before you start

  1. The four kinds, and the one thing to get right

  2. auth can-i, the command that ends the guessing

  3. Read the rules back, two ways

  4. Generate the same objects imperatively

  5. Prove it from inside a Pod, with a real 403

  6. ClusterRoles, cluster-scoped resources, and cluster-admin

  7. Clean up, and one deletion trap

Official sources