OpenTelemetry tracing

Enable OpenTelemetry (OTel) tracing capabilities to obtain visibility and track requests as they pass through your API gateway to distributed backends.

OTel provides a standardized protocol for reporting traces, and a standardized collector through which to recieve metrics. Additionally, OTel supports exporting metrics to several types of distributed tracing platforms. For the full list of supported platforms, see the OTel GitHub respository.

To get started, deploy an OTel collector and agents to your Gloo Edge cluster to trace requests, and modify your gateway proxy with the OTel tracing configuration. Then, use a tracing provider to collect and visualize the sampled spans.

The OTel integration is supported as a beta feature in Gloo Edge 1.13.0 and later.

This guide uses the Zipkin tracing platform as an example to show how to set up tracing with OTel in Gloo Edge. To set up other tracing platforms, refer to the platform-specific documentation.

Before you begin: Create or update your Gloo Edge installation to version 1.13.0 or later.

  1. Download the otel-config.yaml file, which contains the configmaps, daemonset, deployment, and service for the OTel collector and agents. You can optionally check out the contents to see the OTel collector configuration.

    • For example, in the otel-collector-conf configmap that begins on line 92, the data.otel-agent-config.receivers section enables gRPC and HTTP protocols for data collection. The data.otel-agent-config.exporters section enables logging data to Zipkin for tracing and to the Edge console for debugging.
    • In the otel-collector deployment, you can comment out the ports that begin on line 194 so that only the tracing platform you want to use is enabled, such as Zipkin for this guide.
    • For more information about this configuration, see the OTel documentation. For more information and examples about the exporters you can configure, see the OTel GitHub repo.
    cd ~/Downloads
    open otel-config.yaml
  2. Install the OTel collector and agents into your cluster.

    kubectl apply -n gloo-system -f otel-config.yaml
  3. Verify that the OTel collector and agents are deployed in your cluster. Because the agents are deployed as a daemonset, the number of agent pods equals the number of worker nodes in your cluster.

    kubectl get pods -n gloo-system

    Example output:

    NAME                              READY   STATUS    RESTARTS   AGE
    discovery-db9fbdd-4wsg8           1/1     Running   0          3h
    gateway-proxy-b5995db59-bvl9d     1/1     Running   0          3h
    gloo-56c78bb857-6v7vz             1/1     Running   0          3h
    otel-agent-dpdmd                  3/3     Running   0          35s
    otel-collector-64d8c966c5-ptpfn   1/1     Running   0          35s
  4. Install Zipkin, which receives tracing data from the Zipkin exporter in your OTel setup.

    kubectl -n gloo-system create deployment --image openzipkin/zipkin zipkin
    kubectl -n gloo-system expose deployments/zipkin --port 9411 --target-port 9411
  5. Create the following Gloo Edge Upstream, Gateway, and VirtualService custom resources.

    • The Upstream defines the OTel network address and port that Envoy reports data to.
    • The Gateway resource modifies your default HTTP gateway proxy with the OTel tracing configuration, which references the OTel upstream.
    • The VirtualService defines a direct response action so that requests to the / path respond with hello world for testing purposes.
    kubectl apply -f- <<EOF
    kind: Upstream
      name: "opentelemetry-collector"
      namespace: gloo-system
      useHttp2: true
          - addr: "otel-collector"
            port: 4317
    kind: Gateway
        app: gloo
      name: gateway-proxy
      namespace: gloo-system
      bindAddress: '::'
      bindPort: 8080
                  namespace: "gloo-system"
                  name: "opentelemetry-collector"
    kind: VirtualService
      name: default
      namespace: gloo-system
          - '*'
          - matchers:
             - prefix: /
              status: 200
              body: 'hello world'
  6. In three separate terminals, port-forward and view logs for the deployed services.

    1. Port-forward the gateway proxy on port 8080.
      kubectl -n gloo-system port-forward deployments/gateway-proxy 8080
    2. Port-forward the Zipkin service on port 9411.
      kubectl -n gloo-system port-forward deployments/zipkin 9411
    3. Open the logs for the OTel collector.
      kubectl -n gloo-system logs deployments/otel-collector -f
  7. In your original terminal, send a request to http://localhost:8080.

    curl http://localhost:8080
  8. In the OTel collector logs, notice the trace for your request that was printed to the log, such as the following example.

    2023-01-13T17:20:20.907Z	info	TracesExporter	{"kind": "exporter", "data_type": "traces", "name": "logging", "#spans": 1}
    2023-01-13T17:20:20.907Z	info	ResourceSpans #0
    Resource SchemaURL: 
    ScopeSpans #0
    ScopeSpans SchemaURL: 
    Span #0
        Trace ID       : 64dbb2328b98cc8d74dcc9be575ff8cb
        Parent ID      : 
        ID             : 53e50df3bd752d67
        Name           : ingress
        Kind           : Server
        Start time     : 2023-01-13 17:20:20.479033 +0000 UTC
        End time       : 2023-01-13 17:20:20.479216 +0000 UTC
        Status code    : Unset
        Status message : 
         -> node_id: Str(gateway-proxy-b5995db59-bvl9d.gloo-system)
         -> zone: Str()
         -> guid:x-request-id: Str(b843b297-848a-95f0-b824-099a521f5c84)
         -> http.url: Str(http://localhost:8080/)
         -> http.method: Str(GET)
         -> downstream_cluster: Str(-)
         -> user_agent: Str(curl/7.79.1)
         -> http.protocol: Str(HTTP/1.1)
         -> peer.address: Str(
         -> request_size: Str(0)
         -> response_size: Str(11)
         -> component: Str(proxy)
         -> http.status_code: Str(200)
         -> response_flags: Str(-)
    	{"kind": "exporter", "data_type": "traces", "name": "logging"}
  9. Open the Zipkin web interface.

  10. In the Zipkin web interface, click Run query to view traces for your requests, and click Show to review the details of the trace.