Hello, I have created a custom Logback appender which sends the log events to a Kafka topic. In order to verify if producing to Kafka was successful, I check the result and do an addWarn("Failed to produce logging", e) if there was an exception. Similarly, I tried to add an addInfo("produced offset:" + matadata.offset()) when a produce is successful. I'm using this appender in Kafka Connect, where I have wrapped it in an AsyncAppender; however, neither message is showing. I also tried printing to System.out / System.err from within the appender with the same (lack of) result: during start up of Connect, I do see addInfo() messages, but during normal processing, everything goes silent. No messages appear on the topic so I assume something went wrong; when testing the setup in a local docker compose, it works, so there must be some problem somewhere. I understand that this may be due to the combination with Kafka Connect, my question is: should I expect addInfo() etc. to show up in normal appender processing (i.e. calling it from within append() or is this internal logging for use only in appender start() ? What would be the standard way for an appender to report errors during append()? Note: due to circumstances beyond my control, I'm currently stuck on Logback 1.2.11 . Thanks in advance for any tips, kind regards, Ton