In this chapter, we laid out the foundations of Logstash. We walked you through the steps to install and configure Logstash to set up basic data pipelines, and studied Logstash's architecture.
We also learned about the ingest node that was introduced in Elastic 5.x, which can be used instead of a dedicated Logstash setup. We saw how the ingest node can be used to preprocess documents before the actual indexing takes place, and also studied its different APIs.
In the next chapter, we will show you how a rich set of filters brings Logstash closer to the other real-time and near real-time stream processing frameworks with zero coding.