Apache Druid has no native OpenTelemetry receiver. Use its built-in StatsD emitter to push metrics over UDP to the OpenTelemetry Collector statsd receiver, which forwards them to SigNoz.
Prerequisites
- Access to
conf/druid/_common/common.runtime.propertiesin your Druid cluster - An instance of SigNoz (either Cloud or Self-Hosted)
- OpenTelemetry Collector Contrib installed and running
Setup
Step 1: Create the collector config
Create druid-metrics-collection-config.yaml in the same directory as your docker-compose.yml:
receivers:
statsd:
endpoint: 0.0.0.0:8125
aggregation_interval: 10s
processors:
resourcedetection/system:
detectors: ["system"]
system:
hostname_sources: ["os"]
resource:
attributes:
- key: service.name
value: apache-druid
action: upsert
exporters:
otlp/druid:
endpoint: "${env:OTLP_DESTINATION_ENDPOINT}"
tls:
insecure: false
headers:
"signoz-ingestion-key": "${env:SIGNOZ_INGESTION_KEY}"
service:
pipelines:
metrics/druid:
receivers: [statsd]
processors: [resourcedetection/system, resource]
exporters: [otlp/druid]
Step 2: Add the collector service
Add the otelcol service to your docker-compose.yml:
otelcol:
container_name: 'otelcol'
image: 'otel/opentelemetry-collector-contrib:0.150.1'
volumes:
- './druid-metrics-collection-config.yaml:/etc/otelcol/config.yaml'
ports:
- '8125:8125/udp'
environment:
- 'OTLP_DESTINATION_ENDPOINT=ingest.<region>.signoz.cloud:443'
- 'SIGNOZ_INGESTION_KEY=<your-ingestion-key>'
command:
- '--config'
- '/etc/otelcol/config.yaml'
Verify these values:
<region>: Your SigNoz Cloud region<your-ingestion-key>: Your SigNoz ingestion key
Step 3: Configure Druid
Add to your environment file. If druid_extensions_loadList already exists, append "statsd-emitter" to it rather than replacing the array:
druid_extensions_loadList=["druid-histogram", "druid-datasketches", "druid-lookups-cached-global", "postgresql-metadata-storage", "statsd-emitter"]
druid_emitter=statsd
druid_emitter_statsd_hostname=otelcol
druid_emitter_statsd_port=8125
otelcol is the collector's service name in docker-compose.yml. Docker Compose resolves it via built-in DNS.
Step 4: Start the stack
docker compose up -d
Step 1: Configure the SigNoz collector
If you deploy via the SigNoz k8s-infra Helm chart, apply a values override to enable StatsD ingestion:
otelDeployment:
config:
receivers:
statsd:
endpoint: 0.0.0.0:8125
aggregation_interval: 10s
processors:
resource/druid:
attributes:
- key: service.name
value: apache-druid
action: upsert
service:
pipelines:
metrics/statsd:
receivers: [statsd]
processors: [resource/druid]
exporters: [otlp]
ports:
statsd-udp:
enabled: true
containerPort: 8125
servicePort: 8125
hostPort: 8125
protocol: UDP
Apply it with Helm:
helm upgrade <release-name> signoz/k8s-infra -n <collector-namespace> --values override-values.yaml
Step 2: Expose UDP port via ClusterIP Service
Create this Service in the Collector's namespace. Druid pods resolve the Collector at otel-collector-statsd.<collector-namespace>.svc.cluster.local:
apiVersion: v1
kind: Service
metadata:
name: otel-collector-statsd
namespace: <collector-namespace>
spec:
selector:
app.kubernetes.io/component: otel-deployment
ports:
- protocol: UDP
port: 8125
targetPort: 8125
Replace <collector-namespace> with the namespace where the Collector runs.
Step 3: Allow ingress via NetworkPolicy
Allow UDP from the Druid namespace to the Collector pod:
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
name: allow-druid-to-otel-statsd
namespace: <collector-namespace>
spec:
podSelector:
matchLabels:
app.kubernetes.io/component: otel-deployment
policyTypes:
- Ingress
ingress:
- from:
- namespaceSelector:
matchLabels:
kubernetes.io/metadata.name: druid
ports:
- protocol: UDP
port: 8125
Step 4: Configure Druid
Add to conf/druid/_common/common.runtime.properties. If druid.extensions.loadList already exists, append "statsd-emitter" to it rather than replacing the array:
druid.extensions.loadList=["statsd-emitter"]
druid.emitter=statsd
druid.emitter.statsd.hostname=otel-collector-statsd.<collector-namespace>.svc.cluster.local
druid.emitter.statsd.port=8125
Replace <collector-namespace> with the namespace where the Collector runs.
Step 5: Restart Druid
Restart Druid pods:
kubectl rollout restart deployment -n <druid-namespace>
The StatsD emitter prefixes every metric with the emitting node type. query/time from the broker arrives as druid.broker.query.time.<datasource>.<queryType>. Pattern: druid.<nodetype>.<metric> where <nodetype> is one of broker, coordinator, historical, middleManager, or router.
Some coordinator metrics also include the host and port of the emitting node, for example druid.coordinator.segment.dropQueue.count.<host>.<port>. You may see this suffix when building dashboards or alerts on segment-level metrics.
Validate
- Open SigNoz.
- Go to Metrics > Metrics Explorer.
- Search for
druid.to confirm metrics flow.
Troubleshooting
Metrics not appearing in SigNoz
- Network reachability: Confirm Druid resolves the Collector hostname and that UDP port
8125is reachable. Runtcpdumpon the Collector node to verify UDP packets arrive. - Kubernetes network policies: Check that policies allow UDP from the Druid namespace to the Collector pod on port
8125. - Extension loading: Confirm
druid.extensions.loadListcontains"statsd-emitter". A malformed array incommon.runtime.propertiesstops all metric emission.
Next Steps
- Import the Apache Druid dashboard.
- Set up alerts on coordinator segment queue metrics or, if you use Kafka-based ingestion,
druid.<node>.ingest.kafka.lag.
Get Help
If you need help with the steps in this topic, please reach out to us on SigNoz Community Slack.
If you are a SigNoz Cloud user, please use in product chat support located at the bottom right corner of your SigNoz instance or contact us at cloud-support@signoz.io.