Monitoring extensions with custom metrics in Kyma

Create a deployment and service for a sample application that exposes a metrics endpoint.

1. Create a new namespace called monitoring-exercise:

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   kubectl create namespace monitoring-exercise

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2. Create a new deployment called hello-kyma in the monitoring-exercise namespace:

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   kubectl apply -n monitoring-exercise -f https://raw.githubusercontent.com/SAP-samples/kyma-runtime-learning-journey/main/unit_8/hello-kyma-deployment-svc.yaml

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3. Verify the successful creation of the deployment:

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   kubectl get deployments -n monitoring-exercise

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   You should see the following output:

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   NAME         READY   UP-TO-DATE   AVAILABLE   AGE
   hello-kyma   1/1     1            1           2m

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4. Port-forward the hello-kyma service to your local machine:

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   kubectl port-forward -n monitoring-exercise svc/hello-kyma 8080:8080

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   Leave this terminal window open and open http://localhost:8080/metrics in a new browser tab. You should see a lot of metrics being exposed by the hello-kyma application.

5. Stop the port-forwarding by pressing Ctrl+C in the terminal window.

Create a deployment and service for a sample application that exposes a metrics endpoint.

1. Create a new namespace called monitoring-exercise:

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   kubectl create namespace monitoring-exercise

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2. Create a new deployment called hello-kyma in the monitoring-exercise namespace:

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   kubectl apply -n monitoring-exercise -f https://raw.githubusercontent.com/SAP-samples/kyma-runtime-learning-journey/main/unit_8/hello-kyma-deployment-svc.yaml

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3. Verify the successful creation of the deployment:

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   kubectl get deployments -n monitoring-exercise

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   You should see the following output:

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   NAME         READY   UP-TO-DATE   AVAILABLE   AGE
   hello-kyma   1/1     1            1           2m

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4. Port-forward the hello-kyma service to your local machine:

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   kubectl port-forward -n monitoring-exercise svc/hello-kyma 8080:8080

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   Leave this terminal window open and open http://localhost:8080/metrics in a new browser tab. You should see a lot of metrics being exposed by the hello-kyma application.

5. Stop the port-forwarding by pressing Ctrl+C in the terminal window.

Configure Prometheus to scrape the metrics endpoint and use Prometheus UI to query the metrics.

1. Create a ServiceMonitor resource for the hello-kyma service:

   1. In a new file called hello-kyma-servicemonitor.yaml, add the following content:
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      apiVersion: monitoring.coreos.com/v1
      kind: ServiceMonitor
      metadata:
        namespace: kyma-system
        name: monitoring-hello-kyma
        labels:
           app: hello-kyma
      spec:
        selector:
           matchLabels:
              app: hello-kyma
        endpoints:
           - port: http
        namespaceSelector:
           any: true

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   2. Apply the ServiceMonitor resource to the kyma-system namespace:
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      kubectl apply -n kyma-system -f hello-kyma-servicemonitor.yaml

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   3. Verify that the ServiceMonitor resource was created successfully:
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      kubectl get servicemonitors -n kyma-system

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2. Verify that Prometheus is scraping the metrics endpoint of the hello-kyma service:

   1. Open the Prometheus UI by running the following command:
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      kubectl port-forward -n kyma-system svc/monitoring-prometheus 9090:9090

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   2. Open http://localhost:9090/targets in a new browser tab. You should see serviceMonitor/kyma-system/monitoring-hello-kyma listed as a target.
   3. Open http://localhost:9090/graph and enter the following query:
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      promhttp_metric_handler_requests_total{service="hello-kyma", code="200"}

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      This query will return the number of successful requests to the hello-kyma service. You should see a graph for the last 5 minutes.

   4. Stop the port-forwarding by pressing Ctrl+C in the terminal window.

Use Grafana to visualize metrics.

1. Open the Grafana UI by running the following command:

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   kubectl port-forward -n kyma-system svc/monitoring-grafana 3000:80

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2. Open http://localhost:3000 in a new browser tab.

3. On the left side, click the Explore button.

4. In the Explore view, click the Add Query button.

5. In the Query field, enter the following query:

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   rate(promhttp_metric_handler_requests_total{service="hello-kyma", code="200"}[1m])

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   This query will return the number of successful requests to the hello-kyma service per minute.

   Note

   To learn more about Prometheus Query Language (PromQL), see Prometheus Query Language.