Java

The dashboards use two incompatible metric families:

JMX and JMX - Kubernetes require Prometheus JMX Exporter metrics such as jmx_exporter_build_info and jvm_memory_pool_bytes_used.
JVM by OpenTelemetry requires metrics from the OpenTelemetry Java Agent.

JMX Exporter

Load the JMX Exporter Java agent and scrape its endpoint:

toml

[[instances]]
urls = ["http://127.0.0.1:9404/metrics"]
url_label_key = "instance"
url_label_value = "{{.Host}}"
labels = { job = "order-service" }

Preserve job and instance, which are dashboard variables.

OpenTelemetry Java Agent

The real-data test used OpenTelemetry Java Agent 2.28.1, OTLP gRPC, and an OTel Collector:

bash

export JAVA_TOOL_OPTIONS="-javaagent:/opt/opentelemetry-javaagent.jar"
export OTEL_SERVICE_NAME="order-service"
export OTEL_EXPORTER_OTLP_ENDPOINT="http://otel-collector:4317"
export OTEL_EXPORTER_OTLP_PROTOCOL="grpc"
export OTEL_METRICS_EXPORTER="otlp"
java -jar app.jar

Collector:

yaml

receivers:
  otlp:
    protocols:
      grpc:
        endpoint: 0.0.0.0:4317
processors:
  batch: {}
exporters:
  prometheus:
    endpoint: 0.0.0.0:9464
service:
  pipelines:
    metrics:
      receivers: [otlp]
      processors: [batch]
      exporters: [prometheus]

Categraf:

toml

[[instances]]
urls = ["http://otel-collector:9464/metrics"]
url_label_key = "instance"
url_label_value = "{{.Host}}"
labels = { job = "java-otel" }

Verify jvm_memory_used_bytes and jvm_gc_duration_seconds_* before importing the OpenTelemetry dashboard.