[Docs] Link to AWS SDK documentation for requests logging (elastic#100491) (elastic#100749)

Co-authored-by: David Turner [email protected]

Author: tlrx

docs/reference/snapshot-restore/repository-s3.asciidoc

@@ -234,8 +234,30 @@ using the {ref}/repo-analysis-api.html[repository analysis API]. If this API
 does not complete successfully, or indicates poor performance, then your
 storage system is not fully compatible with AWS S3 and therefore unsuitable for
 use as a snapshot repository. However, these checks do not guarantee full
-compatibility. Incompatible error codes and consistency or performance issues
-may be rare and hard to reproduce.
+compatibility.
+
+Most storage systems can be configured to log the details of their interaction
+with {es}. If you are investigating a suspected incompatibility with AWS S3, it
+is usually simplest to collect these logs and provide them to the supplier of
+your storage system for further analysis. If the incompatibility is not clear
+from the logs emitted by the storage system, configure {es} to log every
+request it makes to the S3 API by <<configuring-logging-levels,setting the
+logging level>> of the `com.amazonaws.request` logger to `DEBUG`:
+
+[source,console]
+----
+PUT /_cluster/settings
+{
+  "persistent": {
+    "logger.com.amazonaws.request": "DEBUG"
+  }
+}
+----
+// TEST[skip:we don't really want to change this logger]
+
+The supplier of your storage system will be able to analyse these logs to determine the problem. See
+the https://docs.aws.amazon.com/sdk-for-java/v1/developer-guide/java-dg-logging.html[AWS Java SDK]
+documentation for further information.
 
 [[repository-s3-repository]]
 ==== Repository settings