I’m trying to send GELF messages to the UDP input on my Graylog server, using a custom C++ library that I wrote. Some of the messages are being silently ignored. Is there a log somewhere that I can look at, which will tell me if the packets are being received, and if so, why they are being dropped? I tried tailing the log output of the docker container, but nothing relating to my messages appears there.
Alternately, is there a standardized tool available to validate a GELF message, to determine what about it, if anything, might be broken?