What is RBAC in Kubernetes and how does it work?

RBAC (Role-Based Access Control) in Kubernetes is an access management mechanism that allows restricting user and service permissions based on roles. In Kubernetes, RBAC defines who (a user, group, or service account) can perform which actions (e.g., create, read, update resources) on which objects within the cluster.

Main components of RBAC:

• Role — a set of rules (permissions) that define access to resources within a namespace.
• ClusterRole — similar to Role, but applied at the cluster level.
• RoleBinding — binds a Role to a user or group within a specific namespace.
• ClusterRoleBinding — binds a ClusterRole to a user or group at the cluster level.

Example: if you want to give a user read access to pods in the dev namespace, you create a Role with the necessary permissions and a RoleBinding that associates this role with the user.

Thus, RBAC provides flexible and secure access management, allowing minimization of permissions and adherence to the principle of least privilege.