OpenTelemetry Metrics Format

The OpenTelemetry receiver supports ingesting agent metrics by meter-system. The OAP can load the configuration at bootstrap. If the new configuration is not well-formed, the OAP may fail to start up. The files are located at $CLASSPATH/otel-rules.

Supported handlers:

• otlp: OpenTelemetry gRPC service handler.

Notice: Set SW_OTEL_RECEIVER=default through system environment or change receiver-otel/selector=${SW_OTEL_RECEIVER:default} to activate the OpenTelemetry receiver.

The rule file should be in YAML format, defined by the scheme described in MAL. Note: receiver-otel only supports the group, defaultMetricLevel, and metricsRules nodes of the scheme due to its push mode.

To activate the otlp handler and relevant rules of istio:

receiver-otel:
  selector: ${SW_OTEL_RECEIVER:default}
  default:
    enabledHandlers: ${SW_OTEL_RECEIVER_ENABLED_HANDLERS:"otlp-metrics"}
    enabledOtelMetricsRules: ${SW_OTEL_RECEIVER_ENABLED_OTEL_METRICS_RULES:"istio-controlplane"}

The receiver adds label with key node_identifier_host_name to the collected data samples, and its value is from net.host.name (or host.name for some OTLP versions) resource attributes defined in OpenTelemetry proto, for identification of the metric data.

Notice: In the resource scope, dots (.) in the attributes' key names are converted to underscores (_), whereas in the metrics scope, they are not converted.