Datadog

Point Datadog agents, dd-trace-* SDKs, and DogStatsD clients at observability-stack by changing an endpoint URL or environment variable. No application code changes required.

Which path applies to your setup?

If you run…	Use
Datadog Agent on your hosts, forwarding app traces	Reconfigure the agent (or route traffic to the compat collector on 8126).
Apps instrumented with a `dd-trace-*` SDK sending directly	Set `DD_AGENT_HOST` and related env vars on each app.
DogStatsD clients (`statsd`/`dogstatsd` libraries)	Point them at port 8125/udp.

All three paths require the compat overlay to be enabled. See the overview.

Protocol support

Signal	Default port	Upstream stability
Traces	8126/tcp	Alpha
Metrics	8126/tcp	Development
Logs	8126/tcp	Development
DogStatsD metrics	8125/udp	Beta

Stability note: “Development” is the least mature OpenTelemetry Collector stability tier. APIs and behavior may change without notice. Evaluate carefully before routing production metric or log traffic through the Datadog receiver. Traces are “Alpha” — more mature but still pre-Beta.

For current per-endpoint behavior, consult the upstream datadogreceiver README.

Configuration

`dd-trace-*` SDKs

Datadog maintains tracer libraries for Python (dd-trace-py), Java (dd-trace-java), Go (dd-trace-go), Ruby (dd-trace-rb), JavaScript/Node (dd-trace-js), .NET (dd-trace-dotnet), and PHP (dd-trace-php). All support endpoint override via environment variables, though variable names may differ slightly by library.

Common environment variables:

Variable	Default	Purpose
`DD_AGENT_HOST`	`localhost`	Agent hostname
`DD_TRACE_AGENT_PORT`	`8126`	Agent trace port
`DD_TRACE_AGENT_URL`	—	Full URL override (takes precedence)
`DD_SERVICE`	—	Service name (maps to OTel `service.name`)
`DD_ENV`	—	Environment (maps to OTel `deployment.environment`)
`DD_VERSION`	—	Version (maps to OTel `service.version`)

export DD_AGENT_HOST=<observability-stack-host>
export DD_TRACE_AGENT_PORT=8126
export DD_SERVICE=my-service
export DD_ENV=prod
export DD_VERSION=1.2.3

Consult each library’s documentation for language-specific configuration.

Datadog Agent

If you run a Datadog Agent on your hosts, update its config to forward to observability-stack’s compat collector, or change your app’s DD_AGENT_HOST to bypass the agent entirely.

DogStatsD clients

DogStatsD clients send UDP to port 8125. Most DogStatsD libraries accept STATSD_HOST / STATSD_PORT env vars or constructor arguments:

export STATSD_HOST=<observability-stack-host>
export STATSD_PORT=8125

observability-stack uses the upstream statsdreceiver, which supports DogStatsD tag extensions (#tag1:value1,tag2:value2).

Canonical attribute mapping

These are the three Datadog fields with well-known, universally-used OTel equivalents — the Datadog unified service tagging fields.

Datadog	OTel
`service`	`service.name`
`env`	`deployment.environment`
`version`	`service.version`

The receiver also performs internal translations for HTTP, database, gRPC, and AWS SDK spans that don’t require user action. For all other attributes, consult the upstream datadogreceiver README and Datadog’s tagging documentation.

Deployment modes

Greenfield — observability-stack binds port 8126; no Datadog Agent on the host.
Side-by-side — Datadog Agent on 8126, compat collector on a remapped port. Set COMPAT_DATADOG_APM_PORT=8127 and configure a subset of apps with DD_TRACE_AGENT_PORT=8127. Useful for A/B validation during migration.
Full replacement — Datadog Agent decommissioned, observability-stack on 8126.

Verify

Send a DogStatsD metric and confirm the compat collector accepts it:

echo "test.metric:1|c|#env:test" | nc -u -w1 localhost 8125

For traces, point a dd-trace-* application at observability-stack and dispatch a request. Traces appear under APM or Discover Traces in OpenSearch Dashboards within seconds.

Caveats

128-bit trace IDs are feature-gated upstream (receiver.datadogreceiver.Enable128BitTraceID, off by default). Traces originating in an OpenTelemetry-instrumented service and passing through a Datadog-instrumented service may not correlate without this flag.
Metric temporality: dd-trace-* emits delta metrics. Some backends expect cumulative. Add a deltatocumulativeprocessor to the pipeline if needed.

Not covered

Live processes, profiling, network monitoring — no open-source OpenTelemetry receivers exist for these Datadog products.
Synthetic monitoring — not a telemetry-ingest concern.
Datadog UI features (notebooks, SLOs, monitors) — use OpenSearch Dashboards equivalents.