Running Logstash as a service spawns different processes

Elastic Stack Logstash
1

When running logstash as a service on Ubuntu 14.04 using following command:-

sudo initctl start logstash

Observing that a new logstash process is spawned after every 15 seconds.

If logstash has started with process id 1025, then after 15 seconds the process id is different from 1025 and subsequently process id's keep on changing.

2

Sounds like it's not starting properly, so init is respawning it. Check the LS logs for why.

3

There was some error in logs due to which it kept respawning it.
It would be better if this could somewhere be mentioned in the docs so that users do not suspect anything wrong with it.