This guide will show you how to take an instant backup in Stash.
At first, you need to have a Kubernetes cluster, and the
kubectl command-line tool must be configured to communicate with your cluster. If you do not already have a cluster, you can create one by using kind.
Stash in your cluster following the steps here.
You should be familiar with the following
To keep everything isolated, we are going to use a separate namespace called
demo throughout this tutorial.
$ kubectl create ns demo namespace/demo created
Here, we are going to configure backup for a Deployment. At first, we are going to deploy a Deployment with a PVC and generate some sample data in it. Then, we are going to configure backup for the Deployment using Stash.
Below is the YAML of the Deployment and PVC that we are going to create,
kind: PersistentVolumeClaim apiVersion: v1 metadata: name: source-data namespace: demo spec: accessModes: - ReadWriteOnce storageClassName: standard resources: requests: storage: 2Gi --- apiVersion: apps/v1 kind: Deployment metadata: labels: app: stash-demo name: stash-demo namespace: demo spec: replicas: 1 selector: matchLabels: app: stash-demo template: metadata: labels: app: stash-demo name: busybox spec: containers: - args: ["echo sample_data > /source/data/data.txt && sleep 3000"] command: ["/bin/sh", "-c"] image: busybox imagePullPolicy: IfNotPresent name: busybox volumeMounts: - mountPath: /source/data name: source-data restartPolicy: Always volumes: - name: source-data persistentVolumeClaim: claimName: source-data
The above Deployment will automatically create a
data.txt file in
/source/data directory and write some sample data in it.
Let’s create the Deployment and PVC we have shown above.
$ kubectl apply -f https://github.com/stashed/docs/raw/v2022.09.29/docs/guides/use-cases/instant-backup/examples/deployment.yaml persistentvolumeclaim/source-data created deployment.apps/stash-demo created
Now, wait for the pod of the Deployment to go into
$ kubectl get pod -n demo NAME READY STATUS RESTARTS AGE stash-demo-859d96f6bd-fxr7l 1/1 Running 0 81s
Verify that the sample data has been created in
/source/data directory using the following command,
$ kubectl exec -n demo stash-demo-859d96f6bd-fxr7l -- cat /source/data/data.txt sample_data
Create Secret and Repository:
We are going to store our backed up data into a GCS bucket. We have to create a Secret and a Repository object with access credentials and backend information respectively.
For GCS backend, if the bucket does not exist, Stash needs
Storage Object Adminrole permissions to create the bucket. For more details, please check the following guide.
Let’s create a secret called
gcs-secret with access credentials of our desired GCS backend,
$ echo -n 'changeit' > RESTIC_PASSWORD $ echo -n '<your-project-id>' > GOOGLE_PROJECT_ID $ cat /path/to/downloaded-sa-key.json > GOOGLE_SERVICE_ACCOUNT_JSON_KEY $ kubectl create secret generic -n demo gcs-secret \ --from-file=./RESTIC_PASSWORD \ --from-file=./GOOGLE_PROJECT_ID \ --from-file=./GOOGLE_SERVICE_ACCOUNT_JSON_KEY secret/gcs-secret created
Now, create a
Repository using this secret. Below is the YAML of
Repository crd we are going to create,
apiVersion: stash.appscode.com/v1alpha1 kind: Repository metadata: name: gcs-repo namespace: demo spec: backend: gcs: bucket: appscode-qa prefix: /stash/instant/deployment storageSecretName: gcs-secret
Let’s create the
Repository object that we have shown above,
$ kubectl apply -f https://github.com/stashed/docs/raw/v2022.09.29/docs/guides/use-cases/instant-backup/examples/repository.yaml repository.stash.appscode.com/gcs-repo created
Now, we are ready to backup our sample data into this backend.
We have to create a
BackupConfiguration crd targeting the
stash-demo Deployment that we have deployed earlier. Then, Stash will inject a sidecar container into the target. It will also create a
CronJob to take periodic backup of
/source/data directory of the target.
Below is the YAML of the
BackupConfiguration object that we are going to create and specify that this
BackupConfiguration will take backup in every 40 minutes.
apiVersion: stash.appscode.com/v1beta1 kind: BackupConfiguration metadata: name: deployment-backup namespace: demo spec: repository: name: gcs-repo schedule: "*/40 * * * *" target: ref: apiVersion: apps/v1 kind: Deployment name: stash-demo volumeMounts: - name: source-data mountPath: /source/data paths: - /source/data retentionPolicy: name: 'keep-last-5' keepLast: 5 prune: true
Let’s create the
BackupConfiguration object that we have shown above,
$ kubectl apply -f https://github.com/stashed/docs/raw/v2022.09.29/docs/guides/use-cases/instant-backup/examples/backupconfiguration.yaml backupconfiguration.stash.appscode.com/deployment-backup created
If everything goes well, Stash will inject a sidecar container into the
stash-demo Deployment to take backup of
/source/data directory. Let’s check that the sidecar has been injected successfully,
$ kubectl get pod -n demo NAME READY STATUS RESTARTS AGE stash-demo-9bff9fd4f-xvt77 2/2 Running 0 57s
Look at the pod. It now has 2 containers. If you view the resource definition of this pod, you will see that there is a container named
stash which is running
It will also create a
CronJob with the schedule specified in
spec.schedule field of
Verify that the
CronJob has been created using the following command,
$ kubectl get backupconfiguration -n demo NAME TASK SCHEDULE PAUSED AGE deployment-backup */40 * * * * 6m41s
Now, we are going to trigger an instant backup of the volumes of the Deployment that we have configured in the previous section. To do that, we have to create a
BackupSession object pointing to the respective
Below is the YAML of the
BackupSession crd that we are going to create,
apiVersion: stash.appscode.com/v1beta1 kind: BackupSession metadata: labels: stash.appscode.com/backup-configuration: deployment-backup name: deployment-backupsession namespace: demo spec: invoker: apiGroup: stash.appscode.com kind: BackupConfiguration name: deployment-backup
metadata.labelsholds the respective
BackupConfigurationname as a label. Stash backup sidecar container use this label to watch only the BackupSessions of that
BackupConfiguration. You must provide the label in the following format:
stash.appscode.com/backup-configuration: <BackupConfiguration name>
spec.invokersection indicates the
BackupConfigurationobject whose target will be backed up instantly for this
Let’s create the
BackupSession object that we have have shown above,
$ kubectl apply -f https://github.com/stashed/docs/raw/v2022.09.29/docs/guides/use-cases/instant-backup/examples/backupsession.yaml backupsession.stash.appscode.com/deployment-backupsession created
If everything goes well, the stash sidecar inside the Deployment will take a backup instantly.
Wait for BackupSession to Succeed:
Run the following command to watch
$ watch -n 3 kubectl get backupsession -n demo Every 3.0s: kubectl get backupsession -n demo suaas-appscode: Wed Jul 10 17:18:52 2019 NAME INVOKER-TYPE INVOKER-NAME PHASE AGE deployment-backupsession BackupConfiguration deployment-backup Succeeded 21s
We can see from the above output that the instant backup session has succeeded. Now, we are going to verify that the backed up data has been stored in the backend.
Once a backup is complete, Stash will update the respective
Repository crd to reflect the backup. Check that the repository
gcs-repo has been updated by the following command,
$ kubectl get repository -n demo gcs-repo NAME INTEGRITY SIZE SNAPSHOT-COUNT LAST-SUCCESSFUL-BACKUP AGE gcs-repo true 24 B 1 116s 10m
Now, if we navigate to the GCS bucket, we are going to see backed up data has been stored in
stash/instant/deployment directory as specified by
spec.backend.gcs.prefix field of
Note: Stash keeps all the backed up data encrypted. So, data in the backend will not make any sense until they are decrypted.
kubectl delete -n demo deployment stash-demo kubectl delete -n demo backupconfiguration deployment-backup kubectl delete -n demo backupsession deployment-backupsession kubectl delete -n demo repository gcs-secret kubectl delete -n demo secret gcs-secret kubectl delete -n demo pvc --all