---
title: Customizing Istio Metrics with Telemetry API
description: This task shows you how to customize the Istio metrics with Telemetry API.
weight: 10
keywords: [telemetry,metrics,customize]
owner: istio/wg-policies-and-telemetry-maintainers
test: yes
---

Telemetry API has been in Istio as a first-class API for quite sometime now.
Previously, users had to configure metrics in the `telemetry` section of the Istio configuration.

This task shows you how to customize the metrics that Istio generates with Telemetry API.

## Before you begin

[Install Istio](/docs/setup/) in your cluster and deploy an application.

Telemetry API can not work together with `EnvoyFilter`. For more details please checkout this [issue](https://github.com/istio/istio/issues/39772).

* Starting with Istio version `1.18`, the Prometheus `EnvoyFilter` will not be
  installed by default, and instead `meshConfig.defaultProviders` is used to
  enable it. Telemetry API should be used to further customize the telemetry
  pipeline.

* For versions of Istio before `1.18`, you should install with the following `IstioOperator` configuration:

    {{< text yaml >}}
    apiVersion: install.istio.io/v1alpha1
    kind: IstioOperator
    spec:
      values:
        telemetry:
          enabled: true
          v2:
            enabled: false
    {{< /text >}}

## Override metrics

The `metrics` section provides values for the metric dimensions as expressions,
and allows you to remove or override the existing metric dimensions.
You can modify the standard metric definitions using `tags_to_remove` or by re-defining a dimension.

1. Remove `grpc_response_status` tags from `REQUEST_COUNT` metric

    {{< text yaml >}}
    apiVersion: telemetry.istio.io/v1alpha1
    kind: Telemetry
    metadata:
      name: remove-tags
      namespace: istio-system
    spec:
      metrics:
        - providers:
            - name: prometheus
          overrides:
            - match:
                mode: CLIENT_AND_SERVER
                metric: REQUEST_COUNT
              tagOverrides:
                grpc_response_status:
                  operation: REMOVE
    {{< /text >}}

1. Add custom tags for `REQUEST_COUNT` metric

    {{< text yaml >}}
    apiVersion: telemetry.istio.io/v1alpha1
    kind: Telemetry
    metadata:
      name: custom-tags
      namespace: istio-system
    spec:
      metrics:
        - overrides:
            - match:
                metric: REQUEST_COUNT
                mode: CLIENT
              tagOverrides:
                destination_x:
                  value: upstream_peer.labels['app'].value
            - match:
                metric: REQUEST_COUNT
                mode: SERVER
              tagOverrides:
                source_x:
                  value: downstream_peer.labels['app'].value
          providers:
            - name: prometheus
    {{< /text >}}

## Disable metrics

1. Disable all metrics by following configuration:

    {{< text yaml >}}
    apiVersion: telemetry.istio.io/v1alpha1
    kind: Telemetry
    metadata:
      name: remove-all-metrics
      namespace: istio-system
    spec:
      metrics:
        - providers:
            - name: prometheus
          overrides:
            - disabled: true
              match:
                mode: CLIENT_AND_SERVER
                metric: ALL_METRICS
    {{< /text >}}

1. Disable `REQUEST_COUNT` metrics by following configuration:

    {{< text yaml >}}
    apiVersion: telemetry.istio.io/v1alpha1
    kind: Telemetry
    metadata:
      name: remove-request-count
      namespace: istio-system
    spec:
      metrics:
        - providers:
            - name: prometheus
          overrides:
            - disabled: true
              match:
                mode: CLIENT_AND_SERVER
                metric: REQUEST_COUNT
    {{< /text >}}

1. Disable `REQUEST_COUNT` metrics for client by following configuration:

    {{< text yaml >}}
    apiVersion: telemetry.istio.io/v1alpha1
    kind: Telemetry
    metadata:
      name: remove-client
      namespace: istio-system
    spec:
      metrics:
        - providers:
            - name: prometheus
          overrides:
            - disabled: true
              match:
                mode: CLIENT
                metric: REQUEST_COUNT
    {{< /text >}}

1. Disable `REQUEST_COUNT` metrics for server by following configuration:

    {{< text yaml >}}
    apiVersion: telemetry.istio.io/v1alpha1
    kind: Telemetry
    metadata:
      name: remove-server
      namespace: istio-system
    spec:
      metrics:
        - providers:
            - name: prometheus
          overrides:
            - disabled: true
              match:
                mode: SERVER
                metric: REQUEST_COUNT
    {{< /text >}}

## Verify the results

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](/docs/examples/bookinfo/) example.
{{< /tip >}}

Use the following command to verify that Istio generates the data for your new
or modified dimensions:

{{< text bash >}}
$ istioctl x es "$(kubectl get pod -l app=productpage -o jsonpath='{.items[0].metadata.name}')" -oprom | grep istio_requests_total | grep -v TYPE |grep -v 'reporter="destination"'
{{< /text >}}

{{< text bash >}}
$ istioctl x es "$(kubectl get pod -l app=details -o jsonpath='{.items[0].metadata.name}')" -oprom | grep istio_requests_total
{{< /text >}}

For example, in the output, locate the metric `istio_requests_total` and
verify it contains your new dimension.

{{< tip >}}
It might take a short period of time for the proxies to start applying the config. If the metric is not received,
you may retry sending requests after a short wait, and look for the metric again.
{{< /tip >}}