Send your data to your GELF input

Sending the log to logstash with netcat

echo '{"test_version": "1.1","test_host":"example.org","short_message":"A short message that helps you identify what is going on","test_level":1,"user_id":9001,"some_info":"foo","some_env_var":"bar"}' | gzip | nc -u -w 1 your-logstash-host your-port

View the data

Take a look in your kibana for your message, note UDP doesnt guarantee delivery