Add troubleshooting guide for 429 errors when using the Elastic Cloud Managed OTLP Endpoint

solutions/observability/get-started/quickstart-elastic-cloud-otel-endpoint.md

@@ -162,7 +162,10 @@ You must format your API key as `"Authorization": "ApiKey <api-key-value-here>"`
 
 ### Error: too many requests
 
-The Managed OTLP endpoint has per-project rate limits in place. If you reach this limit, reach out to our [support team](https://support.elastic.co). Refer to [Rate limiting](opentelemetry://reference/motlp.md#rate-limiting) for more information.
+If you see HTTP `429 Too Many Requests` errors when sending data through the Elastic Cloud Managed OTLP Endpoint (mOTLP) endpoint, your project might be hitting ingest rate limits.
+
+Refer to the dedicated [429 errors when using the Elastic Cloud Managed OTLP Endpoint](/troubleshoot/ingest/opentelemetry/429-errors-motlp.md) troubleshooting guide for details on causes, rate limits, and solutions.
+
 
 ## Provide feedback
 

troubleshoot/ingest/opentelemetry/429-errors-motlp.md

@@ -0,0 +1,123 @@
+---
+navigation_title: 429 errors when using the mOTLP endpoint
+description: Resolve HTTP 429 `Too Many Requests` errors when sending data through the Elastic Cloud Managed OTLP (mOTLP) endpoint in Elastic Cloud Serverless or Elastic Cloud Hosted (ECH).
+applies_to:
+  stack:
+  serverless:
+    observability:
+  product:
+    edot_collector:
+products:
+  - id: cloud-serverless
+  - id: cloud-hosted
+  - id: observability
+  - id: edot-collector
+---
+
+# 429 errors when using the Elastic Cloud Managed OTLP Endpoint
+
+When sending telemetry data through the {{motlp}} (mOTLP), you might encounter HTTP `429 Too Many Requests` errors. These indicate that your ingest rate has temporarily exceeded the rate or burst limits configured for your {{ecloud}} project.
+
+This issue can occur in both {{serverless-full}} and {{ech}} (ECH) environments.
+
+## Symptoms
+
+You might see log messages similar to the following in your EDOT Collector output or SDK logs:
+
+```json
+{
+  "code": 8,
+  "message": "error exporting items, request to <ingest endpoint> responded with HTTP Status Code 429"
+}
+```
+
+In some cases, you may also see warnings or backpressure metrics increase in your Collector’s internal telemetry (for example, queue length or failed send count).
+
+## Causes
+
+A 429 status means that the rate of requests sent to the Managed OTLP endpoint has exceeded allowed thresholds. This can happen for several reasons:
+
+* Your telemetry pipeline is sending data faster than the allowed ingest rate.
+* Bursts of telemetry data exceed the short-term burst limit, even if your sustained rate is within limits.
+
+    The specific limits depend on your environment:
+
+    | Deployment type | Rate limit | Burst limit |
+    |-----------------|------------|-------------|
+    | Serverless      | 15 MB/s    | 30 MB/s     |
+    | ECH             | Depends on deployment size and available {{es}} capacity | Depends on deployment size and available {{es}} capacity |
+
+    Exact limits depend on your subscription tier.
+    Refer to the [Rate limiting section](opentelemetry://reference/motlp.md#rate-limiting) in the mOTLP reference documentation for details.
+
+* In {{ech}}, the {{es}} capacity for your deployment might be underscaled for the current ingest rate.
+* In {{serverless-full}}, rate limiting should not result from {{es}} capacity, since the platform automatically scales ingest capacity. If you suspect a scaling issue, [contact Elastic Support](contact-support.md).
+* Multiple Collectors or SDKs are sending data concurrently without load balancing or backoff mechanisms.
+
+## Resolution
+
+To resolve 429 errors, identify whether the bottleneck is caused by ingest limits or {{es}} capacity.
+
+### Scale your deployment or request higher limits
+
+If you’ve confirmed that your ingest configuration is stable but still encounter 429 errors:
+
+* {{serverless-full}}: [Contact Elastic Support](contact-support.md) to request an increase in ingest limits.
+* {{ech}} (ECH): Increase your {{es}} capacity by scaling or resizing your deployment:
+  * [Scaling considerations](../../../deploy-manage/production-guidance/scaling-considerations.md)
+  * [Resize deployment](../../../deploy-manage/deploy/cloud-enterprise/resize-deployment.md)
+  * [Autoscaling in ECE and ECH](../../../deploy-manage/autoscaling/autoscaling-in-ece-and-ech.md)
+
+After scaling, monitor your ingest metrics to verify that the rate of accepted requests increases and 429 responses stop appearing.
+
+### Reduce ingest rate or enable backpressure
+
+Lower the telemetry export rate by enabling batching and retry mechanisms in your EDOT Collector or SDK configuration. For example:
+
+```yaml
+processors:
+  batch:
+    send_batch_size: 1000
+    timeout: 5s
+
+exporters:
+  otlp:
+    retry_on_failure:
+      enabled: true
+      initial_interval: 1s
+      max_interval: 30s
+      max_elapsed_time: 300s
+```
+
+These settings help smooth out spikes and automatically retry failed exports after rate-limit responses.
+
+### Enable retry logic and queueing
+
+To minimize data loss during temporary throttling, configure your exporter to use a sending queue and retry logic. For example:
+
+```yaml
+exporters:
+  otlp:
+    sending_queue:
+      enabled: true
+      num_consumers: 10
+      queue_size: 1000
+    retry_on_failure:
+      enabled: true
+```
+
+This ensures the Collector buffers data locally while waiting for the ingest endpoint to recover from throttling.
+
+## Best practices
+
+To prevent 429 errors and maintain reliable telemetry data flow, implement these best practices:
+
+* Monitor internal Collector metrics (such as `otelcol_exporter_send_failed` and `otelcol_exporter_queue_capacity`) to detect backpressure early.
+* Distribute telemetry load evenly across multiple Collectors instead of sending all data through a single instance.
+* When possible, enable batching and compression to reduce payload size.
+* Keep retry and backoff intervals conservative to avoid overwhelming the endpoint after a temporary throttle.
+
+## Resources
+
+* [{{motlp}} reference](opentelemetry://reference/motlp.md)
+* [Quickstart: Send OTLP data to Elastic Serverless or {{ech}}](../../../solutions/observability/get-started/quickstart-elastic-cloud-otel-endpoint.md)

troubleshoot/toc.yml

@@ -171,6 +171,7 @@ toc:
               - file: ingest/opentelemetry/edot-sdks/misconfigured-sampling-sdk.md
           - file: ingest/opentelemetry/no-data-in-kibana.md
           - file: ingest/opentelemetry/connectivity.md
+          - file: ingest/opentelemetry/429-errors-motlp.md
           - file: ingest/opentelemetry/contact-support.md
       - file: ingest/logstash.md
         children: