k8s RBAC token

Kubernetes Role-Based Access Control (RBAC) allows you to define roles and permissions for users or service accounts within a Kubernetes cluster. RBAC token authentication is a method to authenticate users based on tokens. In this article, we will guide you through the process of implementing RBAC token authentication in Kubernetes.

### Steps to Implement k8s RBAC token:

| Step | Description |
|------|-------------|
| 1. | Generate a Service Account |
| 2. | Get the Service Account Token |
| 3. | Create a Cluster Role |
| 4. | Bind the Cluster Role to the Service Account |

### Step 1: Generate a Service Account

A service account is a special type of account used for applications running in pods.

```bash
kubectl create serviceaccount
```

### Step 2: Get the Service Account Token

To get the token associated with the service account, you can run the following command:

```bash
kubectl get serviceaccount -o=jsonpath='{.secrets[0].name}'
```

This command will return the secret name that contains the token.

### Step 3: Create a Cluster Role

A ClusterRole defines a set of permissions for objects within the cluster.

Here is an example of a ClusterRole definition in a file named `cluster-role.yaml`:

```yaml
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name:
rules:
- apiGroups: [""]
resources: ["pods"]
verbs: ["get", "list", "watch"]
```

Apply the ClusterRole using the following command:

```bash
kubectl apply -f cluster-role.yaml
```

### Step 4: Bind the Cluster Role to the Service Account

To bind the ClusterRole to the ServiceAccount, you can create a ClusterRoleBinding:

```yaml
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name:
subjects:
- kind: ServiceAccount
name:
namespace: default
roleRef:
kind: ClusterRole
name:
apiGroup: rbac.authorization.k8s.io
```

Apply the ClusterRoleBinding using the following command:

```bash
kubectl apply -f cluster-role-binding.yaml
```

Once you have completed these steps, the service account will be able to authenticate using the token associated with it. The ClusterRole that you have created will define the permissions that the service account has within the cluster.

By following these steps, you can successfully implement RBAC token authentication in Kubernetes, allowing you to control access to resources based on roles and permissions.