> ## Documentation Index > Fetch the complete documentation index at: https://private-7c7dfe99-fix-nav-issues.mintlify.site/llms.txt > Use this file to discover all available pages before exploring further. # Generate synthetic OpenTelemetry data with telemetrygen > Use telemetrygen to send diverse synthetic logs, traces and metrics to a ClickStack OpenTelemetry collector [`telemetrygen`](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/cmd/telemetrygen) is the OpenTelemetry Collector Contrib data generator. It emits synthetic OTLP logs, traces and metrics, and exposes flags that let you shape the data: multiple services, log severities, span statuses and child spans, and different metric types. Use it to confirm that a ClickStack OpenTelemetry collector is accepting data and that varied, realistic events surface in the ClickStack UI. This guide assumes the collector is already running with OTLP endpoints on `4317` (gRPC) and `4318` (HTTP).

Prerequisites

This guide assumes you have completed the [Getting Started Guide for Managed ClickStack](/clickstack/deployment/managed) and have an OpenTelemetry collector running with the OTLP gRPC (`4317`) and HTTP (`4318`) endpoints reachable from the machine you run `telemetrygen` on. If you [secured the collector](/clickstack/ingesting-data/collector#securing-the-collector) with an `OTLP_AUTH_TOKEN`, keep that value handy.

Install telemetrygen

Run `telemetrygen` from its Docker image (no install required). Define a small wrapper so the commands below stay readable; `--add-host` lets the container reach a collector listening on the host: ```shell theme={null} telemetrygen() { docker run --rm --add-host=host.docker.internal:host-gateway \ ghcr.io/open-telemetry/opentelemetry-collector-contrib/telemetrygen:latest "$@" } export OTEL_ENDPOINT=host.docker.internal:4317 ``` Or install the binary with Go and target `localhost` instead: ```shell theme={null} go install github.com/open-telemetry/opentelemetry-collector-contrib/cmd/telemetrygen@latest export OTEL_ENDPOINT=localhost:4317 ```

Set environment variables

Export the auth token if the collector is secured: ```shell theme={null} export OTLP_AUTH_TOKEN= ``` **Unsecured collector** The ClickStack OpenTelemetry collector is unauthenticated by default. If you haven't followed [Securing the collector](/clickstack/ingesting-data/collector#securing-the-collector) to set an `OTLP_AUTH_TOKEN`, drop the `--otlp-header` line from the helper below. Define a small `tg` helper so each command only specifies what varies (service, severity, status, attributes): ```shell theme={null} tg() { local signal=$1; shift; telemetrygen "$signal" \ --otlp-endpoint ${OTEL_ENDPOINT} --otlp-insecure \ --otlp-header "authorization=\"${OTLP_AUTH_TOKEN}\"" \ --rate 5 --duration 30s "$@"; } ```

Generate logs

Send logs as a realistic mix of severities across services, mostly informational with a warning and an error rather than one uniform stream: ```shell theme={null} tg logs --service frontend --severity-text Info --severity-number 9 --body "GET /api/products 200" \ --otlp-attributes 'deployment.environment="production"' \ --telemetry-attributes 'http.method="GET"' --telemetry-attributes 'http.status_code="200"' tg logs --service checkout --severity-text Warn --severity-number 13 --body "retrying payment authorization" \ --otlp-attributes 'deployment.environment="production"' \ --telemetry-attributes 'http.method="POST"' tg logs --service payment --severity-text Error --severity-number 17 --body "payment gateway timeout" \ --otlp-attributes 'deployment.environment="production"' \ --telemetry-attributes 'http.status_code="500"' ``` The most useful log flags: * `--service` sets `service.name` so events are attributable to a service. * `--severity-text` and `--severity-number` set the level (`severity-number` ranges from 1 to 24). * `--body` sets the log message. * `--otlp-attributes` sets resource-level attributes (`key="value"`, `key=true`, or `key=`). * `--telemetry-attributes` sets per-record attributes.

Generate traces

Send multi-span traces from several healthy services plus one failing dependency. This gives the Service Map a realistic shape, mostly healthy with one erroring service, and populates the error views: ```shell theme={null} # Healthy services: the bulk of the traffic, all spans Ok for svc in frontend checkout cart; do tg traces --service "$svc" --child-spans 3 --span-duration 80ms --status-code Ok \ --otlp-attributes 'deployment.environment="production"' \ --telemetry-attributes "http.route=\"/$svc\"" done # One slow dependency returning errors tg traces --service payment --child-spans 3 --span-duration 450ms --span-links 1 --status-code Error \ --otlp-attributes 'deployment.environment="production"' \ --telemetry-attributes 'http.route="/charge"' ``` The most useful trace flags: * `--child-spans` generates that many child spans per trace, giving each trace real depth. * `--span-duration` sets how long each span lasts (for example `120ms`, `2s`). * `--status-code` is one of `Unset`, `Error`, `Ok` (or `0`, `1`, `2`). Use `Error` to exercise error views. * `--span-links` adds links between spans. * `--workers` runs several generators in parallel for a higher, more varied volume.

Generate metrics

Send the three common metric types so dashboards have counters, gauges, and a distribution. Unlike some generators, `telemetrygen` honors `--duration` for metrics, so no manual stop is needed: ```shell theme={null} tg metrics --service frontend --metric-type Sum --otlp-metric-name http.server.requests --aggregation-temporality cumulative tg metrics --service frontend --metric-type Gauge --otlp-metric-name system.memory.usage tg metrics --service payment --metric-type Histogram --otlp-metric-name http.server.duration ``` `--metric-type` accepts `Gauge`, `Sum`, `Histogram`, or `ExponentialHistogram`. `--otlp-metric-name` names the series so you can find it in the UI, and `--aggregation-temporality` is `delta` or `cumulative`.

Verify in ClickStack

Open the ClickStack UI from the ClickHouse Cloud console. In the `Search` view, set the time range to `Last 15 minutes` and switch the source between `Logs` and `Traces`. Filter on `ServiceName` to see the `frontend`, `checkout`, `cart`, and `payment` services, and on `SeverityText` to find the warning and error log lines. Open a `payment` trace to see the child spans and the error status. Open the `Chart Explorer`, select `Metrics`, and chart one of the metric names you set above (for example `http.server.requests`) to verify metrics ingestion.

Prerequisites

This guide assumes you have started Open Source ClickStack using the [instructions for the all-in-one image](/clickstack/getting-started/oss), and that the OTLP endpoints (`4317` gRPC and `4318` HTTP) are reachable. You also need the ingestion API key from the HyperDX UI under `Team Settings > API Keys`.

Install telemetrygen

Run `telemetrygen` from its Docker image (no install required). Define a small wrapper so the commands below stay readable; `--add-host` lets the container reach a collector listening on the host: ```shell theme={null} telemetrygen() { docker run --rm --add-host=host.docker.internal:host-gateway \ ghcr.io/open-telemetry/opentelemetry-collector-contrib/telemetrygen:latest "$@" } export OTEL_ENDPOINT=host.docker.internal:4317 ``` Or install the binary with Go and target `localhost` instead: ```shell theme={null} go install github.com/open-telemetry/opentelemetry-collector-contrib/cmd/telemetrygen@latest export OTEL_ENDPOINT=localhost:4317 ```

Set environment variables

Export the ingestion API key: ```shell theme={null} export CLICKSTACK_API_KEY= ``` Define a small `tg` helper so each command only specifies what varies (service, severity, status, attributes): ```shell theme={null} tg() { local signal=$1; shift; telemetrygen "$signal" \ --otlp-endpoint ${OTEL_ENDPOINT} --otlp-insecure \ --otlp-header "authorization=\"${CLICKSTACK_API_KEY}\"" \ --rate 5 --duration 30s "$@"; } ```

Generate logs

Send logs as a realistic mix of severities across services, mostly informational with a warning and an error rather than one uniform stream: ```shell theme={null} tg logs --service frontend --severity-text Info --severity-number 9 --body "GET /api/products 200" \ --otlp-attributes 'deployment.environment="production"' \ --telemetry-attributes 'http.method="GET"' --telemetry-attributes 'http.status_code="200"' tg logs --service checkout --severity-text Warn --severity-number 13 --body "retrying payment authorization" \ --otlp-attributes 'deployment.environment="production"' \ --telemetry-attributes 'http.method="POST"' tg logs --service payment --severity-text Error --severity-number 17 --body "payment gateway timeout" \ --otlp-attributes 'deployment.environment="production"' \ --telemetry-attributes 'http.status_code="500"' ```

Generate traces

Send multi-span traces from several healthy services plus one failing dependency. This gives the Service Map a realistic shape, mostly healthy with one erroring service, and populates the error views: ```shell theme={null} # Healthy services: the bulk of the traffic, all spans Ok for svc in frontend checkout cart; do tg traces --service "$svc" --child-spans 3 --span-duration 80ms --status-code Ok \ --otlp-attributes 'deployment.environment="production"' \ --telemetry-attributes "http.route=\"/$svc\"" done # One slow dependency returning errors tg traces --service payment --child-spans 3 --span-duration 450ms --span-links 1 --status-code Error \ --otlp-attributes 'deployment.environment="production"' \ --telemetry-attributes 'http.route="/charge"' ```

Generate metrics

Send the three common metric types so charts have a counter, a gauge, and a distribution: ```shell theme={null} tg metrics --service frontend --metric-type Sum --otlp-metric-name http.server.requests --aggregation-temporality cumulative tg metrics --service frontend --metric-type Gauge --otlp-metric-name system.memory.usage tg metrics --service payment --metric-type Histogram --otlp-metric-name http.server.duration ``` `--metric-type` accepts `Gauge`, `Sum`, `Histogram`, or `ExponentialHistogram`.

Verify in ClickStack

Visit [http://localhost:8080](http://localhost:8080) to open the ClickStack UI. In the `Search` view, set the time range to `Last 15 minutes` and switch the source between `Logs` and `Traces`. Filter on `ServiceName` to see the `frontend`, `checkout`, `cart`, and `payment` services, and on `SeverityText` to find the warning and error log lines. Open a `payment` trace to see the child spans and the error status. Open the `Chart Explorer`, select `Metrics`, and chart one of the metric names you set above (for example `http.server.requests`) to verify metrics ingestion.