How to add --config.reload.automatic to service file

[TomonoriSoejima]

1 . add the following to /etc/systemd/system/logstash.service

"--config.reload.automatic"

It should look like this once it is added.

ExecStart=/usr/share/logstash/bin/logstash "--path.settings" "/etc/logstash" "--config.reload.automatic"

2. reload the config

   sudo systemctl daemon-reload
   sudo systemctl stop logstash.service
   sudo systemctl start logstash.service