I use Logstash 5.1.
My Logstash restart alone. In /var/log/message i see :
logstash: Sending Logstash's logs to /var/log/logstash which is now configured via log4j2.properties systemd: logstash.service holdoff time over, scheduling restart.
I don't have any log in /var/log/logstash/logstash-plain.log
All my conf file in /etc/logstash/conf.d are good.
Any one have an idea ?