monitoring-custom-metrics

Expose Custom Metrics in Kyma

Overview

This example shows how to expose custom metrics to Prometheus with a Golang service in Kyma. To do so, follow these steps:

1. Expose a sample application serving metrics on the 8081 port.
2. Access the exposed metrics in Prometheus.

Prerequisites

• Kyma as the target deployment environment.
• Deployed custom kube-prometheus-stack as described in the prometheus example.

Installation

Expose a sample metrics application

1. Export your Namespace as a variable. Replace the {namespace} placeholder in the following command and run it:

   export K8S_NAMESPACE="{namespace}"

2. Ensure that your Namespace has Istio sidecar injection enabled. This example assumes that the metrics are exposed in a strict mTLS mode:

   kubectl label namespace ${K8S_NAMESPACE} istio-injection=enabled

3. Deploy the service:

   kubectl apply -f https://raw.githubusercontent.com/kyma-project/examples/main/prometheus/monitoring-custom-metrics/deployment/deployment.yaml -n $K8S_NAMESPACE

4. Deploy the ServiceMonitor:

   kubectl apply -f https://raw.githubusercontent.com/kyma-project/examples/main/prometheus/monitoring-custom-metrics/deployment/service-monitor.yaml

Access the exposed metrics in Prometheus

1. Run the port-forward command on the monitoring-prometheus service:

   kubectl -n ${K8S_NAMESPACE} port-forward $(kubectl -n ${K8S_NAMESPACE} get service -l app=kube-prometheus-stack-prometheus -oname) 9090

All the sample-metrics endpoints appear as Targets under http://localhost:9090/targets#job-sample-metrics list.

2. Use either cpu_temperature_celsius or hd_errors_total in the expression field under http://localhost:9090/graph.
3. Click the Execute button to check the values scraped by Prometheus.

Cleanup

Run the following commands to completely remove the example and all its resources from the cluster:

1. Remove ServiceMonitor in the kyma-system Namespace.

   kubectl delete servicemonitor -l example=monitoring-custom-metrics -n kyma-system

2. Run the following command to completely remove the example service and all its resources from the cluster:

   kubectl delete all -l example=monitoring-custom-metrics -n $K8S_NAMESPACE