The obvious approach in such case is to: 1) Trace your program and see what methods are called and what they return. 2) I never used log4j2 but I supposed that due to what it does it would probably catch and silently "drop" many of its own internal exceptions. Check if you can enable internal log4j2 debugging. 3) Verify network traffic to check whether your program is indeed connecting to your indexer and tries to send something or not.
... View more