docs/tracing.md

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# Apache Accumulo Tracing Example

This tutorial uses the [TracingExample.java] Java class to create an OpenTelemetry
span in the TracingExample application and then create and read entries from Accumulo.
Tracing output should show up in logs for the TracingExample class and the Accumulo client,
and logs for the Accumulo server processes.

## Setup

  1. Download the OpenTelemetry [JavaAgent] jar file and place it into the `/path/to/accumulo/lib/` directory.
  2. Add the property `general.opentelemetry.enabled=true` to accumulo.properties
  3. Set the following environment variables in your environment:
  
    JAVA_TOOL_OPTIONS="-javaagent:/path/to/accumulo/lib/opentelemetry-javaagent-1.12.1.jar"
    OTEL_TRACES_EXPORTER="logging"

## Run the Example

  1. Start Accumulo
  2. Run the Tracing Example:
  
    $ ./bin/runex client.TracingExample --createtable --deletetable --create --read --table traceTest

[JavaAgent]: https://search.maven.org/remotecontent?filepath=io/opentelemetry/javaagent/opentelemetry-javaagent/1.12.1/opentelemetry-javaagent-1.12.1.jar
[TracingExample.java]: ../src/main/java/org/apache/accumulo/examples/client/TracingExample.java