OBSDOCS-1272/TRACING-4573: add documentation for Prometheus Remote Write Exporter

Author: iblancasa

observability/otel/otel-collector/otel-collector-connectors.adoc

@@ -119,3 +119,8 @@ include::snippets/technology-preview.adoc[]
 # ...
 ----
 <1> Defines the flush interval of the generated metrics. Defaults to `15s`.
+
+[role="_additional-resources"]
+[id="additional-resources_otel-collector-connectors_{context}"]
+== Additional resources
+* link:https://opentelemetry.io/docs/specs/otlp/[OpenTelemetry Protocol (OTLP) documentation]

observability/otel/otel-collector/otel-collector-exporters.adoc

@@ -189,6 +189,48 @@ include::snippets/technology-preview.adoc[]
 <8> Defines how long metrics are exposed without updates. The default is `5m`.
 <9> Adds the metrics types and units suffixes. Must be disabled if the monitor tab in Jaeger console is enabled. The default is `true`.
 
+[id="prometheus-remote-write-exporter_{context}"]
+== Prometheus Remote Write Exporter
+
+The Prometheus Remote Write Exporter exports metrics to compatible back ends.
+
+:FeatureName: The Prometheus Remote Write Exporter
+include::snippets/technology-preview.adoc[]
+
+.OpenTelemetry Collector custom resource with an enabled Prometheus Remote Write Exporter
+[source,yaml]
+----
+# ...
+  config: |
+    exporters:
+      prometheusremotewrite:
+        endpoint: "https://my-prometheus:7900/api/v1/push" # <1>
+        tls: # <2>
+          ca_file: ca.pem
+          cert_file: cert.pem
+          key_file: key.pem
+        target_info: true # <3>
+        export_created_metric: true # <4>
+        max_batch_size_bytes: 3000000 # <5>
+    service:
+      pipelines:
+        metrics:
+          exporters: [prometheusremotewrite]
+# ...
+----
+<1> Endpoint for sending the metrics.
+<2> Server-side TLS configuration. Defines paths to TLS certificates.
+<3> When set to `true`, creates a `target_info` metric for each resource metric.
+<4> When set to `true`, exports a `_created` metric for the Summary, Histogram, and Monotonic Sum metric points.
+<5> Maximum size of the batch of samples that is sent to the remote write endpoint. Exceeding this value results in batch splitting. The default value is `3000000`, which is approximately 2.861 megabytes.
+
+[WARNING]
+====
+* This exporter drops non-cumulative monotonic, histogram, and summary OTLP metrics.
+
+* You must enable the `--web.enable-remote-write-receiver` feature flag on the remote Prometheus instance. Without it, pushing the metrics to the instance using this exporter fails.
+====
+
 [id="kafka-exporter_{context}"]
 == Kafka Exporter
 
@@ -230,3 +272,8 @@ include::snippets/technology-preview.adoc[]
 <5> The client-side TLS configuration. Defines paths to the TLS certificates. If omitted, TLS authentication is disabled.
 <6> Disables verifying the server's certificate chain and host name. The default is `+false+`.
 <7> ServerName indicates the name of the server requested by the client to support virtual hosting.
+
+[role="_additional-resources"]
+[id="additional-resources_otel-collector-exporters_{context}"]
+== Additional resources
+* link:https://opentelemetry.io/docs/specs/otlp/[OpenTelemetry Protocol (OTLP) documentation]

observability/otel/otel-collector/otel-collector-extensions.adoc

@@ -458,3 +458,8 @@ include::snippets/technology-preview.adoc[]
 ----
 
 <1> Specifies the HTTP endpoint that serves zPages. Use `localhost:` to make it available only locally, or `":"` to make it available on all network interfaces. The default is `localhost:55679`.
+
+[role="_additional-resources"]
+[id="additional-resources_otel-collector-extensions_{context}"]
+== Additional resources
+* link:https://opentelemetry.io/docs/specs/otlp/[OpenTelemetry Protocol (OTLP) documentation]

observability/otel/otel-collector/otel-collector-processors.adoc

@@ -558,3 +558,7 @@ config: |
 |Returns errors up the pipeline and drops the payload. Implicit default.
 
 |===
+[role="_additional-resources"]
+[id="additional-resources_otel-collector-processors_{context}"]
+== Additional resources
+* link:https://opentelemetry.io/docs/specs/otlp/[OpenTelemetry Protocol (OTLP) documentation]

observability/otel/otel-collector/otel-collector-receivers.adoc

@@ -823,3 +823,8 @@ rules:
 ----
 <1> The service account of the Collector that has the required ClusterRole `otel-collector` RBAC.
 <2> The list of namespaces to collect events from. The default value is empty, which means that all namespaces are collected.
+
+[role="_additional-resources"]
+[id="additional-resources_otel-collector-receivers_{context}"]
+== Additional resources
+* link:https://opentelemetry.io/docs/specs/otlp/[OpenTelemetry Protocol (OTLP) documentation]