Decentralized

The decentralized collector deployment pattern consists of applications—instrumented with an OpenTelemetry SDK using OpenTelemetry protocol (OTLP)—or other collectors (using the OTLP exporter) that send telemetry signals to one or more collectors. Each client-side SDK or downstream collector is configured with a collector location:

1. In the app, the SDK is configured to send OTLP data to a collector.
2. The collector is configured to send telemetry data to one or more backends.

Example

A concrete example of the decentralized collector deployment pattern could look as follows: you manually instrument, say, a Java application to export metrics using the OpenTelemetry Java SDK. In the context of the app, you would set the OTEL_METRICS_EXPORTER to otlp (which is the default value) and configure the OTLP exporter with the address of your collector, for example (in Bash or zsh shell):

export OTEL_EXPORTER_OTLP_ENDPOINT=http://collector.example.com:4318

The collector serving at collector.example.com:4318 would then be configured like so:

• Traces
• Metrics
• Logs

receivers:
  otlp: # the OTLP receiver the app is sending traces to
    protocols:
      grpc:

processors:
  batch:

exporters:
  jaeger: # the Jaeger exporter, to ingest traces to backend
    endpoint: "https://jaeger.example.com:14250"
    insecure: true

service:
  pipelines:
    traces/dev:
      receivers: [otlp]
      processors: [batch]
      exporters: [jaeger]

receivers:
  otlp: # the OTLP receiver the app is sending metrics to
    protocols:
      grpc:

processors:
  batch:

exporters:
  prometheusremotewrite: # the PRW exporter, to ingest metrics to backend
    endpoint: "https://prw.example.com/v1/api/remote_write"

service:
  pipelines:
    metrics/prod:
      receivers: [otlp]
      processors: [batch]
      exporters: [prometheusremotewrite]

receivers:
  otlp: # the OTLP receiver the app is sending logs to
    protocols:
      grpc:

processors:
  batch:

exporters:
  file: # the File Exporter, to ingest logs to local file 
    path: "./app42_example.log"
    rotation:

service:
  pipelines:
    logs/dev:
      receivers: [otlp]
      processors: [batch]
      exporters: [file]

If you want to try it out for yourself, you can have a look at the end-to-end Java or Python examples.

Tradeoffs

Pros:

• Simple to get started
• Clear 1:1 mapping between application and collector

Cons:

• Scalability (human and load-wise)
• Inflexible