Logstash pipeline.yml

Question

I was wondering if I config my pipeline.yml with my .files in conf.d directory it's not necessary to run the following command to create indexes on Elastic Search:

bin/logstash -f /etc/logstash/conf.d/myfile.conf

I ask this because whenever I try to run the above command it throws me an error that says an instance is already running, and the only way to run the command is adding --path.settings to the command.