Logstash is used for transforming logs, and you can use many plugins in Logstash. Logstash works with configuration files that contain three main parts: an input part, a filter part, and an output part. In the input part, we can take logs from many sources such as Beats, files, or Kafka. The filter part is used to filter the logs that are shipped from Beats. From my understanding and experience with Logstash, it is usually used for processing logic, meaning I can control what fields should be transferred to Elastic and what fields shouldn't be transferred. This is the main function I use Logstash for. Elastic is a famous open-source searching engine that helps operation teams speed up the investigation process and provides real-time insights for performance reporting.
