RBAC Plan for Kubernetes Cluster

1. Define Roles and Responsibilities

- Identify teams and projects.
- Specify access requirements for resources like Pods, Deployments, and ConfigMaps.
- Group permissions into roles such as developer, admin, viewer.

2. Use Namespaces for Isolation

- Create separate namespaces for each team or project.
- Assign namespace-specific roles using Role and RoleBinding.

3. Create Service Accounts

- Assign service accounts to applications needing API interaction.
- Create service accounts within relevant namespaces for better management.

4. Define Roles and ClusterRoles

- Use Role for namespace-scoped permissions.
- Use ClusterRole for cluster-wide permissions.

5. Bind Roles to Users and Service Accounts

- Use RoleBinding to assign roles within namespaces.
- Use ClusterRoleBinding for cluster-wide role assignments.

6. Implement Least Privilege

- Grant only necessary permissions for each role.
- Periodically review and audit permissions to align with current needs.

7. Monitor and Audit

- Enable Kubernetes auditing to track access and changes.
- Monitor cluster activity using tools like Prometheus and Grafana.

Example YAML Configurations

Role for Developers

apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
  namespace: dev-team
  name: developer-role
rules:
- apiGroups: [""]
  resources: ["pods", "services", "configmaps"]
  verbs: ["get", "list", "create", "update", "delete"]

RoleBinding for Developer Group

apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  namespace: dev-team
  name: developer-binding
subjects:
- kind: Group
  name: dev-team-group
  apiGroup: rbac.authorization.k8s.io
roleRef:
  kind: Role
  name: developer-role
  apiGroup: rbac.authorization.k8s.io

ClusterRole for Admins

apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: cluster-admin-role
rules:
- apiGroups: ["*"]
  resources: ["*"]
  verbs: ["*"]

ClusterRoleBinding for Admin Group

apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: cluster-admin-binding
subjects:
- kind: Group
  name: admin-group
  apiGroup: rbac.authorization.k8s.io
roleRef:
  kind: ClusterRole
  name: cluster-admin-role
  apiGroup: rbac.authorization.k8s.io

ServiceAccount for Applications

apiVersion: v1
kind: ServiceAccount
metadata:
  name: app-service-account
  namespace: dev-team