ElasticSearch is an open-source and distributed search engine which is very much scalable and supports a good amount of enterprise Search use cases.
Introduction to Elasticsearch
ElasticSearch is an open source project, under the Apache License version 2, built on top of Lucene and Java. The source code is located on GitHub, at https://github.com/elastic/elasticsearch.
Behind the ElasticSearch product is a company named Elastic. It’s website is located at https://www.elastic.co/. Elastic is the core developers of the open source project and owns the copyright for it. Additionally, the company provides training, support and a number of commercial add-ons for ElasticSearch.
In other words, ElasticSearch is free to use but there is a company that supports its development. This company also provides services and add-ons which are not free. It’s entirely up to you whether you pay anything in conjunction with using ElasticSearch or not. If you don’t, you will still have access to the full ElasticSearch product, but if you do pay money, you’ll be able to get training, support and/or nice add-ons.
Apart from ElasticSearch, there are a number of other projects within the same ecosystem. Two of those are LogStash and Kibana. LogStash can be used to store logs from various sources in ElasticSearch. Kibana provides functionality to visualize data stored in ElasticSearch in dashboards. Together ElasticSearch, LogStash and Kibana is referred to as the “ELK stack”.
Elasticsearch is a platform for distributed, RESTful search and analysis. It can scale as needed, and you can get started using it right away
ElasticSearch is a Java application built for Java 7 or higher. Therefore, the first step in setting up ElasticSearch is to ensure that you have Java installed and the JAVA_HOME environment variable correctly configured.
To check that you have a compatible version of Java installed, open up a terminal window and type java-version. The output should look something like this:
Running java -version in a console where Java 8 is installed.
$ java -version
java version “1.8.0_25”
Java(TM) SE Runtime Environment (build 1.8.0_25-b17)
Java HotSpot(TM) 64-Bit Server VM (build 25.25-b02, mixed mode)
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