GKE Persistent Disks - Volume Snapshots and Restore

Step-00: Pre-requisites¶

Verify if GKE Cluster is created

Verify if kubeconfig for kubectl is configured in your local terminal

# Configure kubeconfig for kubectl
gcloud container clusters get-credentials <CLUSTER-NAME> --region <REGION> --project <PROJECT>

# Replace Values CLUSTER-NAME, ZONE, PROJECT
gcloud container clusters get-credentials standard-cluster-private-1 --region us-central1 --project kdaida123

Feature: Compute Engine persistent disk CSI Driver
Verify the Feature Compute Engine persistent disk CSI Driver enabled in GKE Cluster.
This is required for mounting the Google Compute Engine Persistent Disks to Kubernetes Workloads in GKE Cluster.

Step-01: Introduction¶

Deploy UMS WebApp with 01-kube-manifests
Create new User (admin102, admin103)
Create Volume Snapshot Kubernetes Objects and Deploy them
Delete User (admin102, admin103)
Deploy PVC Restore 03-Volume-Restore
Verify if after restore 2 more users what we deleted got restored in our UMS App
Clean Up (kubectl delete -R -f )

Step-02: Kubernetes YAML Manifests¶

Project Folder: 01-kube-manifests
No changes to Kubernetes YAML Manifests, same as Section 21-GKE-PD-existing-SC-standard-rwo
01-persistent-volume-claim.yaml
02-UserManagement-ConfigMap.yaml
03-mysql-deployment.yaml
04-mysql-clusterip-service.yaml
05-UserMgmtWebApp-Deployment.yaml
06-UserMgmtWebApp-LoadBalancer-Service.yaml

Step-03: Deploy kube-manifests¶

# Deploy Kubernetes Manifests
kubectl apply -f 01-kube-manifests/

# List Storage Class
kubectl get sc

# List PVC
kubectl get pvc

# List PV
kubectl get pv

# List ConfigMaps
kubectl get configmap

# List Deployments
kubectl get deploy

# List Pods
kubectl get pods

# List Services
kubectl get svc

# Verify Pod Logs
kubectl get pods
kubectl logs -f <USERMGMT-POD-NAME>
kubectl logs -f usermgmt-webapp-6ff7d7d849-7lrg5

Step-04: Verify Persistent Disks¶

Go to Compute Engine -> Storage -> Disks
Search for 4GB Persistent Disk
Observation: Review the below items
Zones: us-central1-c
Type: Balanced persistent disk
In use by: gke-standard-cluster-1-default-pool-db7b638f-j5lk

Step-05: Access Application¶

# List Services
kubectl get svc

# Access Application
http://<ExternalIP-from-get-service-output>
Username: admin101
Password: password101

# Create New User admin102
Username: admin102
Password: password102
First Name: fname102
Last Name: lname102
Email Address: admin102@stacksimplify.com
Social Security Address: ssn102

# Create New User admin103
Username: admin103
Password: password103
First Name: fname103
Last Name: lname103
Email Address: admin103@stacksimplify.com
Social Security Address: ssn103

Step-06: 02-Volume-Snapshot: Create Volume Snapshots¶

Project Folder: 02-Volume-Snapshot

Step-06-01: 01-VolumeSnapshotClass.yaml¶

apiVersion: snapshot.storage.k8s.io/v1
kind: VolumeSnapshotClass
metadata:
  name: my-snapshotclass
driver: pd.csi.storage.gke.io
deletionPolicy: Delete
#parameters: 
#  storage-locations: us-east2

# Optional Note: 
# To use a custom storage location, add a storage-locations parameter to the snapshot class. 
# To use this parameter, your clusters must use version 1.21 or later.

Step-06-02: 02-VolumeSnapshot.yaml¶

apiVersion: snapshot.storage.k8s.io/v1
kind: VolumeSnapshot
metadata:
  name: my-snapshot1
spec:
  volumeSnapshotClassName: my-snapshotclass
  source:
    persistentVolumeClaimName: mysql-pv-claim

Step-06-03: Deploy Volume Snapshot Kubernetes Manifests¶

# Deploy Volume Snapshot Kubernetes Manifests
kubectl apply -f 02-Volume-Snapshot/

# List VolumeSnapshotClass
kubectl get volumesnapshotclass

# Describe VolumeSnapshotClass
kubectl describe volumesnapshotclass my-snapshotclass

# List VolumeSnapshot
kubectl get volumesnapshot

# Describe VolumeSnapshot
kubectl describe volumesnapshot my-snapshot1

# Verify the Snapshots
Go to Compute Engine -> Storage -> Snapshots
Observation:
1. You should find the new snapshot created
2. Review the "Creation Time"
3. Review the "Disk Size: 4GB"

Step-07: Delete users admin102, admin103¶

# List Services
kubectl get svc

# Access Application
http://<ExternalIP-from-get-service-output>
Username: admin101
Password: password101

# Delete Users
admin102
admin103

Step-08: 03-Volume-Restore: Create Volume Restore¶

Project Folder: 03-Volume-Restore

Step-08-01: 01-restore-pvc.yaml¶

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: pvc-restore
spec:
  dataSource:
    name: my-snapshot1
    kind: VolumeSnapshot
    apiGroup: snapshot.storage.k8s.io
  storageClassName: standard-rwo
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 4Gi

Step-08-02: 02-mysql-deployment.yaml¶

Update Claim Name from claimName: mysql-pv-claim to claimName: pvc-restore

apiVersion: apps/v1
kind: Deployment
metadata:
  name: mysql
spec: 
  replicas: 1
  selector:
    matchLabels:
      app: mysql
  strategy:
    type: Recreate 
  template: 
    metadata: 
      labels: 
        app: mysql
    spec: 
      containers:
        - name: mysql
          image: mysql:5.6
          env:
            - name: MYSQL_ROOT_PASSWORD
              value: dbpassword11
          ports:
            - containerPort: 3306
              name: mysql    
          volumeMounts:
            - name: mysql-persistent-storage
              mountPath: /var/lib/mysql    
            - name: usermanagement-dbcreation-script
              mountPath: /docker-entrypoint-initdb.d #https://hub.docker.com/_/mysql Refer Initializing a fresh instance                                        
      volumes: 
        - name: mysql-persistent-storage
          persistentVolumeClaim:
            #claimName: mysql-pv-claim
            claimName: pvc-restore
        - name: usermanagement-dbcreation-script
          configMap:
            name: usermanagement-dbcreation-script

Step-08-03: Deploy Volume Restore Kubernetes Manifests¶

# Deploy Volume Restore Kubernetes Manifests
kubectl apply -f 03-Volume-Restore/

# List PVC
kubectl get pvc

# List PV
kubectl get pv

# List Pods
kubectl get pods

# Restart Deployments (Optional - If ERRORS)
kubectl rollout restart deployment mysql
kubectl rollout restart deployment usermgmt-webapp

# Review Persistent Disk
1. Go to Compute Engine -> Storage -> Disks
2. You should find a new "Balanced persistent disk" created as part of new PVC "pvc-restore"
3. To get the exact Disk name for "pvc-restore" PVC run command "kubectl get pvc"


# Access Application
http://<ExternalIP-from-get-service-output>
Username: admin101
Password: password101
Observation:
1. You should find admin102, admin103 present
2. That proves, we have restored the MySQL Data using VolumeSnapshots and PVC

Step-09: Clean-Up¶

# Delete All (Disks, Snapshots)
kubectl delete -f 01-kube-manifests -f 02-Volume-Snapshot -f 03-Volume-Restore

# List PVC
kubectl get pvc

# List PV
kubectl get pv

# List VolumeSnapshotClass
kubectl get volumesnapshotclass

# List VolumeSnapshot
kubectl get volumesnapshot

# Verify Persistent Disks
1. Go to Compute Engine -> Storage -> Disks -> REFRESH
2. Two disks created as part of this demo is deleted

# Verify Disk Snapshots
1. Go to Compute Engine -> Storage -> Snapshots -> REFRESH
2. There should not be any snapshot which we created as part of this demo.