bootstrap FAQ

Author: SylvainJuge

docs/_edot-sdks/java/faq.md

@@ -7,4 +7,65 @@ parent: EDOT Java
 
 # Frequently Asked Questions on EDOT Java
 
-TODO
+## Does agent requires access to or modification of application code ?
+
+TODO
+
+## How to disable the agent ?
+
+TODO
+
+- remove `-javaagent:` JVM argument
+- use configuration
+
+## How to partially disable the agent
+
+TODO
+
+## How to know if EDOT is attached to a running JVM ?
+
+TODO
+- check JVM logs, agent startup log message might be included
+- check JVM arguments `ps -ef|grep javaagent`
+
+## How to identify the version of EDOT agent ?
+
+When the agent starts, a log message in the standard error provides the agent version: 
+```
+INFO io.opentelemetry.javaagent.tooling.VersionLogger - opentelemetry-javaagent - version: 1.2.3
+```
+
+In addition, the `-javaagent:` JVM argument can provide the path to the agent file name, which _might_ also contain
+the agent version, for example `-javaagent:elastic-otel-javaagent-1.2.3.jar`
+
+When the original agent jar file has been renamed, it is still possible to inspect the `Implementation-Version` entry in `META-INF/MANIFEST.MF` file of the agent jar,
+for example with `unzip -p elastic-otel-javaagent.jar META-INF/MANIFEST.MF|grep 'Implementation-Version'`
+
+## What are the versions of the OpenTelemetry upstream dependencies
+
+TODO
+- SDK
+- Instrumentation
+- Semantic conventions
+
+link to release notes
+
+## Updating EDOT
+
+- general recommendation on updating to latest
+- how to update
+
+- updating EDOT does not require to update OpenTelemetry API/SDK in the application
+
+## Is the agent compatible with other instrumentation agents ?
+
+TODO
+
+## How to instrument un-supported libraries/frameworks
+
+TODO
+
+- use configuration (but limited)
+- use otel API with code modification
+- write an instrumentation extension
+- contribute instrumentation to upstream