E - Elastic Search - Search and Analyze
L - Logstash - Enrich and Transport (can use filebeat instead of log stash) -
K - Kibana - Explore and Visualise (UI dashboard)
Difference between log stash and beats
Beats are lightweight data shippers that you install as agents on your servers to send specific types of operational data to Elasticsearch. Beats have a small footprint and use fewer system resources than Logstash.
Logstash has a larger footprint, but provides a broad array of input, filter, and output plugins for collecting, enriching, and transforming data from a variety of sources.
LOGSTASH
Logstash is an open source data collection engine with real-time pipelining capabilities. Logstash can dynamically unify data from disparate sources and normalize the data into destinations of your choice. Cleanse and democratize all your data for diverse advanced downstream analytics and visualization use cases.
Any type of event can be enriched and transformed with a broad array of input, filter, and output plugins, with many native codecs further simplifying the ingestion process. Logstash accelerates your insights by harnessing a greater volume and variety of data.
BEATS
The Beats are open source data shippers that you install as agents on your servers to send different types of operational data to Elasticsearch. Beats can send data directly to Elasticsearch or send it to Elasticsearch via Logstash, which you can use to enrich or archive the data.
Packetbeat, Metricbeat, and Filebeat are a few examples of Beats. Packetbeat is a network packet analyzer that ships information about the transactions exchanged between your application servers. Metricbeat is a server monitoring agent that periodically collects metrics from the operating systems and services running on your servers. And Filebeat ships log files from your servers.
Setup ELK Stack
Log stash and couch base
https://discuss.elastic.co/t/couchdb-plugin-set-dynamic-type-for-elasticsearch/2293/12