istio.io/content/en/docs/tasks/observability/metrics/querying-metrics/index.md

title	description	weight	keywords	aliases	owner	test
Querying Metrics from Prometheus	This task shows you how to query for Istio Metrics using Prometheus.	30	telemetry metrics	/docs/tasks/telemetry/querying-metrics/ /docs/tasks/telemetry/metrics/querying-metrics/	istio/wg-policies-and-telemetry-maintainers	yes

This task shows you how to query for Istio Metrics using Prometheus. As part of this task, you will use the web-based interface for querying metric values.

The Bookinfo sample application is used as the example application throughout this task.

Before you begin

• Install Istio in your cluster.
• Install the Prometheus Addon.
• Deploy the Bookinfo application.

Querying Istio metrics

1. Verify that the prometheus service is running in your cluster.

   In Kubernetes environments, execute the following command:

   {{< text bash >}} $ kubectl -n istio-system get svc prometheus NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE prometheus ClusterIP 10.109.160.254 9090/TCP 4m {{< /text >}}

2. Send traffic to the mesh.

   For the Bookinfo sample, visit http://$GATEWAY_URL/productpage in your web browser or issue the following command:

   {{< text bash >}} $ curl "http://$GATEWAY_URL/productpage" {{< /text >}}

   {{< tip >}} $GATEWAY_URL is the value set in the Bookinfo example. {{< /tip >}}

3. Open the Prometheus UI.

   In Kubernetes environments, execute the following command:

   {{< text bash >}} $ istioctl dashboard prometheus {{< /text >}}

   Click Graph to the right of Prometheus in the header.

4. Execute a Prometheus query.

   In the "Expression" input box at the top of the web page, enter the text:

   {{< text plain >}} istio_requests_total {{< /text >}}

   Then, click the Execute button.

The results will be similar to:

{{< image link="./prometheus_query_result.png" caption="Prometheus Query Result" >}}

You can also see the query results graphically by selecting the Graph tab underneath the Execute button.

{{< image link="./prometheus_query_result_graphical.png" caption="Prometheus Query Result - Graphical" >}}

Other queries to try:

• Total count of all requests to the productpage service:

  {{< text plain >}} istio_requests_total{destination_service="productpage.default.svc.cluster.local"} {{< /text >}}

• Total count of all requests to v3 of the reviews service:

  {{< text plain >}} istio_requests_total{destination_service="reviews.default.svc.cluster.local", destination_version="v3"} {{< /text >}}

  This query returns the current total count of all requests to the v3 of the reviews service.

• Rate of requests over the past 5 minutes to all instances of the productpage service:

  {{< text plain >}} rate(istio_requests_total{destination_service=~"productpage.*", response_code="200"}[5m]) {{< /text >}}

About the Prometheus addon

The Prometheus addon is a Prometheus server that comes preconfigured to scrape Istio endpoints to collect metrics. It provides a mechanism for persistent storage and querying of Istio metrics.

For more on querying Prometheus, please read their querying docs.

Cleanup

• Remove any istioctl processes that may still be running using control-C or:

  {{< text bash >}} $ killall istioctl {{< /text >}}

• If you are not planning to explore any follow-on tasks, refer to the Bookinfo cleanup instructions to shutdown the application.