Creating and Managing a Deployment

1. In Kyma dashboard, go to the default namespace.

2. Go to Workloads → Deployments and choose the Create button.

   

3. Specify the Deployment's name and the container's image. Use the following data:

   Field	Value
   Name	hello-kyma
   Docker image	ghcr.io/sap-samples/kyma-runtime-learning-journey/hello-kyma:1.0.0

   

4. To review your Deployment manifest, choose the YAML tab.

   

5. Choose the Create button.

   You're automatically redirected to the Deployment details view. This view includes details about the created Deployment and the associated Pod.

6. See the details of the created Deployment. Scroll down to the Resource Graph section to observe the created Deployment and the managed ReplicaSet and Pod.

   

1. To list all your Deployments, run the following kubectl command:

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   kubectl get deployments

   You see the Deployment that you have created.

   

2. To get the Deployment manifest as YAML, run the following command:

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   kubectl get deployment hello-kyma -o yaml >> hello-kyma-deployment.yaml

   Note

   In this task, you use kubectl to download the Deployment manifest and edit it locally. Although you can use Kyma dashboard to edit the Deployment manifest, it is highly recommended to apply changes from a persisted file and put all manifests under version control. This is not possible with Kyma dashboard.

3. Go to your working directory and open the hello-kyma-deployoment.yaml file.

   

4. To update the Deployment to use a new version of the application, change the current container image to the new version and set the change-cause to document the change.

   1. Add the following image in the template.spec.containers.image field: ghcr.io/sap-samples/kyma-runtime-learning-journey/hello-kyma:1.1.0

   2. Add the following annotation in the spec.template.metadata section:

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      annotations:
        kubernetes.io/change-cause: Upgrade to new release v1.1.0

   

5. Save the file.

6. Apply the updated Deployment manifest.

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   kubectl apply -f hello-kyma-deployment.yaml

7. To verify the update in the rollout history, run the following commands:

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   kubectl rollout history deployment hello-kyma

8. Verify the updated Deployment in the Workloads → Deployments section of Kyma dashboard.

1. To scale the Deployment to three replicas, run:

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   kubectl scale deployment hello-kyma --replicas=3

   Kubernetes creates two additional Pods so that now there are three Pods running.

2. To verify that the Deployment is scaled successfully, run:

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   kubectl get deployment hello-kyma

   

3. To verify it in Kyma dashboard, go to Workloads → Deployments and select the hello-kyma Deployment. Scroll down to the list with Pods.

Imagine that you have deployed a new application version, but it is not working as expected. You can now roll back the Deployment to the previous version.

1. To list the rollout history, run:

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   kubectl rollout history deployment hello-kyma

   You should see two versions of the Deployment.

   

2. Roll back the Deployment by specifying the revision number.

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   kubectl rollout undo deployment hello-kyma --to-revision=1

   If successful, you see the following output: deployment.apps/hello-kyma rolled back

3. List the rollout history again to verify the rollback.

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   kubectl rollout history deployment hello-kyma

   You see if the rollback was successful. Furthermore, the order of the revisions has changed, and it's incremented by one.