I don't know if this is logstash or elastic but 5.6 and 5.4 to some extent are fundamentally broken.
On 5.4 I can't get the KV filter to create any mapping. Opened a topic but no solution.
On 5.6 the netflow codec and KV filter are both broken. Logstash and Elastic are running without errors but no data is sent to Elastic.
This is not a problem with my configs, on 5.4 netflow works and stdout shows no problems with the KV filter. On 5.6.1 and 5.6.2 nothing works, its totally dead. No changes to the system or the configs.
I'm running Ubuntu 16.04 inside virtualbox.
Everything appears to be running, no errors anywhere but for whatever reason no data shows up. I have no clue how to proceed and am about to give up on this.