> ## Documentation Index > Fetch the complete documentation index at: https://notes.kodekloud.com/llms.txt > Use this file to discover all available pages before exploring further. # Demo Connecting a Datasource in Grafana > Guide showing how to configure Grafana to connect to an in-cluster Prometheus datasource, verify services, save and test the connection, and troubleshoot common issues Grafana does not store metrics itself; it visualizes metrics collected and stored elsewhere. To visualize metrics in Grafana you must configure a datasource that points to where those metrics live. In this demo we connect Grafana to a Prometheus instance running inside the cluster. Prerequisites * A Prometheus stack is installed in the `monitoring` namespace (kube-prometheus-stack or similar). * Grafana is running and reachable (exposed via NodePort in this environment). * `kubectl` configured to access the cluster. Verify pods and services Run the following to confirm the Prometheus and Grafana components are running: ```bash theme={null} kubectl get pods -n monitoring kubectl get svc -n monitoring ``` A sample output looks like: ```bash theme={null} # pods NAME READY STATUS RESTARTS AGE kube-prometheus-stack-grafana-84cf9bcd57-9vm7h 2/2 Running 0 12m kube-prometheus-stack-kube-state-metrics-567d4944f-1fpz 1/1 Running 0 12m kube-prometheus-stack-operator-5d9b6cb8d-8hqhx 1/1 Running 0 12m kube-prometheus-stack-prometheus-node-exporter-5r5x7 2/2 Running 0 12m prometheus-kube-prometheus-stack-prometheus-0 2/2 Running 0 12m # services NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) kube-prometheus-stack-grafana NodePort 172.20.151.255 80:30080/TCP kube-prometheus-stack-kube-state-metrics ClusterIP 172.20.6.143 8080/TCP kube-prometheus-stack-operator ClusterIP 172.20.149.171 443/TCP kube-prometheus-stack-prometheus NodePort 172.20.50.36 9090:30900/TCP,8080:30392/TCP kube-prometheus-stack-prometheus-node-exporter ClusterIP 172.20.93.180 9100/TCP prometheus-operated ClusterIP None 9090/TCP ``` Quick summary of important endpoints | Component | Access pattern | Example | | ------------------------ | ------------------------------------------------------- | -------------------------------------------------------------- | | Prometheus (cluster DNS) | `http://..svc.cluster.local:` | `http://prometheus-operated.monitoring.svc.cluster.local:9090` | | Prometheus (NodePort) | Node external access | `NodePort 30900` | | Grafana (NodePort) | Node external access | `NodePort 30080` | Open Grafana and log in Use the Grafana NodePort (or your configured ingress) to reach the Grafana UI and sign in with the credentials for your setup. The image shows a Grafana login screen with fields for email or username and password against a gradient background. The "Log in" button is prominently displayed below the input fields. After login you will arrive at Grafana’s home/dashboard page where you can add data sources and create dashboards. The image shows the Grafana dashboard interface, featuring a welcome message and options for setting up data sources and creating dashboards. There are also links for help and recent blog updates. Add Prometheus as a data source 1. Click Add your first data source (or Add data source). 2. From the list, choose Prometheus. The image shows a Grafana interface with options to add different data sources, including Prometheus, Graphite, InfluxDB, and others. It is organized under categories like time series databases and logging & document databases. Configure the Prometheus connection * Keep the default Name (or give it a descriptive name such as `prometheus-monitoring`). * For the URL, point Grafana to the in-cluster Prometheus service. Use the full service DNS name and port (including scheme): ```bash theme={null} http://prometheus-operated.monitoring.svc.cluster.local:9090 ``` This follows the standard in-cluster DNS pattern: `service-name.namespace.svc.cluster.local:port` It will work regardless of the namespace where Grafana runs, provided DNS resolves and any network policies allow access. The image shows the Grafana interface for configuring a Prometheus data source, including fields for connection settings and authentication methods. Optional settings * Toggle “Default” if you want this Prometheus instance to be the default for new dashboards. * Leave authentication, timeouts, and other advanced settings at their defaults unless you require custom configuration (e.g., TLS, headers, or proxy). Save and test Click Save & Test. On success Grafana will show a green confirmation that it was able to query the Prometheus API. The image shows a Grafana data source configuration screen for Prometheus, with various settings toggles and input fields for performance and connection parameters. There's a notification indicating successful querying of the Prometheus API. If Save & Test fails, verify the following: * The service DNS and port are correct: `http://prometheus-operated.monitoring.svc.cluster.local:9090`. * Prometheus pods are running in the `monitoring` namespace: `kubectl get pods -n monitoring`. * NetworkPolicies, firewall rules, or cluster network ACLs are not preventing in-cluster requests from Grafana to Prometheus. Next steps * Create dashboards and panels that query Prometheus using PromQL. * Import prebuilt Grafana dashboards for Kubernetes or your applications. * Secure access to Grafana (authentication, RBAC, and TLS) before exposing it externally. Links and references * Grafana documentation: [https://grafana.com/docs/](https://grafana.com/docs/) * Prometheus documentation: [https://prometheus.io/docs/](https://prometheus.io/docs/) * Kubernetes DNS and Services: [https://kubernetes.io/docs/concepts/services-networking/dns-pod-service/](https://kubernetes.io/docs/concepts/services-networking/dns-pod-service/)