# Additional instrumentation LLMS index: [llms.txt](/llms.txt) --- The OpenTelemetry Spring Boot starter provides [out of the box instrumentation](../out-of-the-box-instrumentation) that you can augment with additional instrumentations. ## Log4j2 Instrumentation You have to add the OpenTelemetry appender to your `log4j2.xml` file: ```xml ``` You can find more configuration options for the OpenTelemetry appender in the [Log4j](https://github.com/open-telemetry/opentelemetry-java-instrumentation/blob/main/instrumentation/log4j/log4j-appender-2.17/library/README.md) instrumentation library.

Enables the configuration of the Log4j OpenTelemetry appender with an OpenTelemetry instance:

otel:
  instrumentation:
    log4j-appender:
      enabled: true # default: true

In declarative configuration, use the centralized instrumentation lists to enable or disable Log4j:

otel:
  distribution:
    spring_starter:
      instrumentation:
        disabled:
          - log4j_appender

## Instrumentation libraries You can configure other instrumentations using [OpenTelemetry instrumentation libraries](https://github.com/open-telemetry/opentelemetry-java-instrumentation/blob/main/docs/supported-libraries.md#libraries--frameworks).