# Create a Cluster via POC POC resources are designed to help users experience GreenNode services in the best way possible. Conditions for using POC resources: * **Target**: Prepaid users who have been granted a POC wallet * **Funding source:** [**POC Wallet**](https://docs.vngcloud.vn/vng-cloud-document/vn/quan-ly-hoa-don-chi-phi-and-tai-nguyen-tren-vng-cloud/trai-nghiem-billing-and-kenh-thanh-toan/ve-billing-and-payment/thanh-toan/thanh-toan-tai-nguyen-poc) * **Resources:** All resources eligible for POC * **Usage period:** Depends on the duration of the granted POC wallet. *** ### Prerequisites To initialize a **Cluster** and **Deploy** a **Workload**, you need: * At least 1 **VPC** and 1 **Subnet** in **ACTIVE** state. If you do not have a VPC or Subnet yet, please create one following the instructions [here.](https://github.com/vngcloud/docs/blob/main/English/vserver/compute-hcm03-1a/network/virtual-private-cloud-vpc/README.md) * At least 1 **SSH** key in **ACTIVE** state. If you do not have any SSH key, please create one following the instructions [here.](https://github.com/vngcloud/docs/blob/main/English/vserver/compute-hcm03-1a/security/ssh-key-bo-khoa.md) * Installed and configured **kubectl** on your device. Please refer [here](https://kubernetes.io/vi/docs/tasks/tools/install-kubectl/) if you are not sure how to install and use kubectl. Additionally, you should not use a kubectl version that is too old; we recommend using a kubectl version that differs by no more than one version from the cluster version. *** ### Create Cluster A **Cluster in Kubernetes** is a collection of one or more virtual machines (VMs) connected together to run containerized applications. A Cluster provides a unified environment for deploying, managing, and operating containers at scale. To create a Cluster, follow the steps below: **Step 1:** Go to **Step 2:** On the **Overview** screen, select **Activate.** **Step 3:** Wait until we successfully initialize your VKS account. After successful activation, select **Create a Cluster** **Step 4:** On the Cluster creation screen, we have pre-configured information for the Cluster and a **Default Node Group**. You can keep these default values or adjust the desired parameters for your Cluster and Node Group at Cluster Configuration, Default Node Group Configuration, Plugin. **By default, we will create a Public Cluster with Public Node Group for you.** **Step 5:** Select **POC** and then select **Create Kubernetes cluster.** Please wait a few minutes for us to create your Cluster. The Cluster status at this point will be **Creating**. **Step 6:** When the **Cluster** status is **Active**, you can view Cluster information and Node Group information by selecting the Cluster Name in the **Name** column. {% hint style="info" %} **Note:** * When you create a Cluster and choose to use the POC wallet, we automatically create the Control Plane, Node, Volume, and Private Service Endpoint (if you choose to use it) through the POC wallet. For other resources such as: * **PVC:** when creating via yaml, please add the parameter `isPOC: "true"` to the yaml file. See the example below. * **LoadBalancer:** when creating via yaml, please add the annotation `vks.vngcloud.vn/is-poc: "true"` to the yaml file. See the example below. * Since **Load Balancer** and **PVC** resources are managed through YAML, after Stop POC, if your YAML file still has the parameter `isPOC : true or is-poc : true`, in case you delete the Load Balancer from vLB Portal and remove the `load-balancer-id` parameter in yaml, the system will automatically recreate these resources through the POC wallet. To create Load Balancer and PVC with real money, please change the isPOC parameter to false. (`isPOC : false or is-poc : false`). We recommend that you adjust this parameter before performing Stop POC for your Cluster. {% endhint %} *** ### Connect and check Cluster information After the Cluster is successfully created, you can connect and check the Cluster information by following these steps: **Step 1:** Go to [https://vks.console.vngcloud.vn/k8s-cluster](https://vks.console-dev.vngcloud.tech/overview) **Step 2:** The Cluster list is displayed, select the **Download** icon and select **Download Config File** to download the kubeconfig file. This file will give you full access to your Cluster. **Step 3**: Rename this file to config and save it to the **\~/.kube/config** folder **Step 4:** Check the Cluster by running: * Run the following command to check **node** ```bash kubectl get nodes ``` * If the result returns as below, your Cluster was successfully created with 3 nodes. ```bash NAME STATUS ROLES AGE VERSION ng-0e10592c-e70e-404d-a4e8-5e3b80f805e4-834b7 Ready 50m v1.28.8 ng-0e10592c-e70e-404d-a4e8-5e3b80f805e4-cf652 Ready 23m v1.28.8 ng-0f4ed631-1252-49f7-8dfc-386fa0b2d29b-a8ef0 Ready 28m v1.28.8 ``` *** ### Deploy Workload and expose service through vLB Layer 4 or vLB Layer 7 Below are instructions for deploying 2 workloads and exposing them through Load Balancer Layer 4 and Load Balancer Layer 7 on Kubernetes. **Step 1**: **Create Deployment, Service for Nginx app.** * Create file **nginx-service.yaml** with the following content: 
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
  namespace: default
spec:
  replicas: 2
  selector:
    matchLabels:
      unique-label: app1
  template:
    metadata:
      labels:
        unique-label: app1
        same-label: vngcloud
    spec:
      containers:
        - name: nginx-deployment
          image: nginx
          ports:
            - containerPort: 80
              name: http
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: python-http-server
spec:
  replicas: 2
  selector:
    matchLabels:
      app: python-http-server
  template:
    metadata:
      labels:
        app: python-http-server
        same-label: vngcloud
    spec:
      containers:
      - name: python-http-server
        image: python:3.9-slim
        command: ["python", "-m", "http.server", "8080"]
        ports:
        - containerPort: 8080
          name: http
---
apiVersion: v1
kind: Service
metadata:
  name: nginx-service
  namespace: default
  annotations:
    vks.vngcloud.vn/is-poc: "true"      # Parameter specifying that the Load Balancer will be created using the POC wallet
spec:
  ports:
    - port: 80
      targetPort: http
      protocol: TCP
      name: http-server
  selector:
    same-label: vngcloud
  type: LoadBalancer

---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: webapp-02
  namespace: default
  annotations:
    vks.vngcloud.vn/is-poc: "true"      # Parameter specifying that the Load Balancer will be created using the POC wallet
spec:
  ingressClassName: vngcloud
  defaultBackend:
    service:
      name: nginx-service
      port:
        name: http-server
* Deploy this Service by running: ```bash kubectl apply -f nginx-service.yaml ``` * Next, you can check the Deployment by running: ```bash kubectl get svc,deploy,pod -owide ``` *** ### **Create Persistent Volume** * Create file **persistent-volume.yaml** with the following content: ```bash apiVersion: storage.k8s.io/v1 kind: StorageClass metadata: name: my-expansion-storage-class # [1] The StorageClass name, CAN be changed provisioner: bs.csi.vngcloud.vn # The VNG-CLOUD CSI driver name parameters: type: vtype-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx # The volume type UUID isPOC: "true" # Parameter specifying that the Volume will be created using the POC wallet allowVolumeExpansion: true # MUST set this value to turn on volume expansion feature --- apiVersion: v1 kind: PersistentVolumeClaim metadata: name: my-expansion-pvc # [2] The PVC name, CAN be changed spec: accessModes: - ReadWriteOnce resources: requests: storage: 20Gi # [3] The PVC size, CAN be changed, this value MUST be in the valid range of the proper volume type storageClassName: my-expansion-storage-class # [4] The StorageClass name, MUST be the same as [1] --- apiVersion: v1 kind: Pod metadata: name: nginx # [5] The Pod name, CAN be changed spec: containers: - image: nginx imagePullPolicy: IfNotPresent name: nginx ports: - containerPort: 80 protocol: TCP volumeMounts: - mountPath: /var/lib/www/html name: my-volume-name # MUST be the same as [6] volumes: - name: my-volume-name # [6] The volume name, CAN be changed persistentVolumeClaim: claimName: my-expansion-pvc # MUST be the same as [2] readOnly: false ``` * Run the following command to deploy: ```bash kubectl apply -f persistent-volume.yaml ``` *** ### **Create Snapshot** For **Snapshot** resources, you cannot specify snapshot to use the POC wallet from VKS. To create a Snapshot via the POC wallet, on **vServer Portal**, please select **Activate Snapshot**, then on the **Checkout** screen, please select the **POC** wallet. At this point, **all your snapshot resources will be created via the POC wallet**. Therefore, stopping POC needs to be done through **vConsole** or **vServer Portal**. See the image below for reference.
**Install GreenNode Snapshot Controller** * Install Helm version 3.0 or higher. Refer to for installation instructions. * Add this repo to your cluster via: ```bash helm repo add vks-helm-charts https://vngcloud.github.io/vks-helm-charts helm repo update ``` * Then run: ```bash helm install vngcloud-snapshot-controller vks-helm-charts/vngcloud-snapshot-controller \ --replace --namespace kube-system ``` * After the installation is complete, check the status of vngcloud-blockstorage-csi-driver pods: ```bash kubectl get pods -n kube-system ``` For example, the output below means you have successfully installed the snapshot-controller: ```bash NAME READY STATUS RESTARTS AGE snapshot-controller-7fdd984f89-745tg 0/1 ContainerCreating 0 3s snapshot-controller-7fdd984f89-k94wq 0/1 ContainerCreating 0 3s ``` **Create file snapshot.yaml with the following content:** ```bash apiVersion: snapshot.storage.k8s.io/v1 kind: VolumeSnapshotClass metadata: name: my-snapshot-storage-class # [2] The name of the volume snapshot class, CAN be changed driver: bs.csi.vngcloud.vn deletionPolicy: Delete parameters: force-create: "false" --- apiVersion: snapshot.storage.k8s.io/v1 kind: VolumeSnapshot metadata: name: my-snapshot-pvc # [4] The name of the snapshot, CAN be changed spec: volumeSnapshotClassName: my-snapshot-storage-class # MUST match with [2] source: persistentVolumeClaimName: my-expansion-pvc # MUST match with [3] ``` * Run the following command to deploy: ```bash kubectl apply -f snapshot.yaml ``` *** ### **Check PVC and Snapshot** * After successfully applying the files, you can check the list of services and PVC via: ```bash kubectl get sc,pvc,pod -owide ``` ```bash NAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSION AGE storageclass.storage.k8s.io/my-expansion-storage-class bs.csi.vngcloud.vn Delete Immediate true 10m storageclass.storage.k8s.io/sc-iops-200-retain (default) bs.csi.vngcloud.vn Retain Immediate false 2d4h NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE VOLUMEMODE persistentvolumeclaim/my-expansion-pvc Bound pvc-14456f4a-ee9e-435d-a94f-5a2e820954e9 20Gi RWO my-expansion-storage-class 10m Filesystem NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES pod/nginx 1/1 Running 0 10m 172.16.24.203 ng-3f06013a-f6a5-47ba-a51f-bc5e9c2b10a7-ecea1 pod/nginx-app-7f45b65946-t7d7k 1/1 Running 0 94m 172.16.24.202 ng-3f06013a-f6a5-47ba-a51f-bc5e9c2b10a7-ecea1 ``` *** ### Change IOPS of a Persistent Volume To change the IOPS of a Persistent Volume, follow these steps: **Step 1:** Run the command below to list PVCs in your Cluster ```bash kubectl get persistentvolumes ``` **Step 2:** Edit the PVC YAML file ```bash kubectl edit pvc my-expansion-pvc ``` * If you have not changed the IOPS of the Persistent Volume before, add the annotation `bs.csi.vngcloud.vn/volume-type: "volume-type-id"`. For example: below I am changing the IOPS from 200 (Volume type id = vtype-61c3fc5b-f4e9-45b4-8957-8aa7b6029018) to 1000 (Volume type id = vtype-85b39362-a360-4bbb-9afa-a36a40cea748) ```bash apiVersion: v1 kind: PersistentVolumeClaim metadata: annotations: bs.csi.vngcloud.vn/volume-type: "vtype-85b39362-a360-4bbb-9afa-a36a40cea748" kubectl.kubernetes.io/last-applied-configuration: | {"apiVersion":"v1","kind":"PersistentVolumeClaim","metadata":{"annotations":{},"name":"my-expansion-pvc","namespace":"default"},"spec":{"accessModes":["ReadWriteOnce"],"resources":{"requests":{"storage":"20Gi"}},"storageClassName":"my-expansion-storage-class"}} pv.kubernetes.io/bind-completed: "yes" pv.kubernetes.io/bound-by-controller: "yes" volume.beta.kubernetes.io/storage-provisioner: bs.csi.vngcloud.vn volume.kubernetes.io/storage-provisioner: bs.csi.vngcloud.vn creationTimestamp: "2024-04-21T14:16:53Z" finalizers: - kubernetes.io/pvc-protection name: my-expansion-pvc namespace: default resourceVersion: "11041591" uid: 14456f4a-ee9e-435d-a94f-5a2e820954e9 spec: accessModes: - ReadWriteOnce resources: requests: storage: 20Gi storageClassName: my-expansion-storage-class volumeMode: Filesystem volumeName: pvc-14456f4a-ee9e-435d-a94f-5a2e820954e9 status: accessModes: - ReadWriteOnce capacity: storage: 20Gi phase: Bound ``` * If you have previously changed the IOPS, the yaml file will already have the annotation `bs.csi.vngcloud.vn/volume-type: "volume-type-id"`. In this case, edit the annotation to the Volume type ID with the desired IOPS. ### Change Disk Volume of a Persistent Volume To change the Disk Volume size, run the following command: For example: initially the PVC was created with 20 Gi, now I will increase it to 30Gi ```bash kubectl patch pvc my-expansion-pvc -p '{"spec":{"resources":{"requests":{"storage":"30Gi"}}}}' ``` {% hint style="info" %} **Note:** * You can only increase the Disk Volume size. You cannot decrease it. {% endhint %} ### Restore Persistent Volume from Snapshot To restore a Persistent Volume from a Snapshot, follow these steps: * Create file **restore-volume.yaml** with the following content: ```bash apiVersion: v1 kind: PersistentVolumeClaim metadata: name: my-restore-pvc # The name of the PVC, CAN be changed spec: storageClassName: my-expansion-storage-class dataSource: name: my-snapshot-pvc # MUST match with [4] from the section 5.2 kind: VolumeSnapshot apiGroup: snapshot.storage.k8s.io accessModes: - ReadWriteOnce resources: requests: storage: 20Gi ``` After experiencing VKS, if you want to convert these POC resources to real resources, please follow the instructions [here](https://docs.vngcloud.vn/vng-cloud-document/vn/vks/clusters/stop-poc).