Hands-on Lab·Kubernetes and Cloud Native Security Associate
RBAC Fundamentals
RBAC is 30% of the KCSA pool by keyword, more than any other subject. This guide builds the smallest possible working example - a ServiceAccount, a Role, a RoleBinding - and then tests the four edges that define what it can reach.
Security Fundamentals Guide 18 of 42 Beginner
- Kubernetesapiserver v1.36.4, kubelet v1.36.3
- Runtimecontainerd 2.2.6
- CNICilium 1.18.1
- Built withkubeadm v1.36.3
- TimeAbout 18 min
RBAC is stable API. kubectl auth can-i --as= impersonation needs the impersonate verb, which cluster-admin has; it is the fastest audit tool in Kubernetes.
- Host kernel7.0.0-29
| Server Name | IP Address | OS | Roles | CPU | RAM | HDD |
|---|---|---|---|---|---|---|
| CKA5001 | 192.168.0.41 | Ubuntu 26.04 LTS | Control Plane Node (tainted NoSchedule) | 2 Core | 4 GB | 50 GB |
| CKA5001-NODE01 | 192.168.0.42 | Ubuntu 26.04 LTS | Worker Node | 2 Core | 4 GB | 50 GB |
| CKA5001-NODE02 | 192.168.0.43 | Ubuntu 26.04 LTS | Worker Node | 2 Core | 4 GB | 50 GB |
| CKA5001-NODE03 | 192.168.0.44 | Ubuntu 26.04 LTS | Worker Node | 2 Core | 4 GB | 50 GB |
This guide includes
Use this because RBAC is the single largest subject in the KCSA pool. This matters because every grant is built the same way - an identity, a Role and a binding - and the fastest way to audit one is to ask the authoriser rather than read YAML.
- creating an identity and confirming it can do nothing whatsoever
- making the smallest grant that does anything - one Role and one binding
- asking that same identity four questions to find the edges of what it holds
Before you start
- guide 4 - where the default ServiceAccount got a 403.
-
An identity with nothing
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One Role, one binding, one permission
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The four edges