Book Image

Elasticsearch Server - Third Edition

By : Rafal Kuc
Book Image

Elasticsearch Server - Third Edition

By: Rafal Kuc

Overview of this book

ElasticSearch is a very fast and scalable open source search engine, designed with distribution and cloud in mind, complete with all the goodies that Apache Lucene has to offer. ElasticSearch’s schema-free architecture allows developers to index and search unstructured content, making it perfectly suited for both small projects and large big data warehouses, even those with petabytes of unstructured data. This book will guide you through the world of the most commonly used ElasticSearch server functionalities. You’ll start off by getting an understanding of the basics of ElasticSearch and its data indexing functionality. Next, you will see the querying capabilities of ElasticSearch, followed by a through explanation of scoring and search relevance. After this, you will explore the aggregation and data analysis capabilities of ElasticSearch and will learn how cluster administration and scaling can be used to boost your application performance. You’ll find out how to use the friendly REST APIs and how to tune ElasticSearch to make the most of it. By the end of this book, you will have be able to create amazing search solutions as per your project’s specifications.
Table of Contents (18 chapters)
Elasticsearch Server Third Edition
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Preface
Index

Understanding node discovery


When starting your Elasticsearch node, one of the first things that happens is looking for a master node that has the same cluster name and is visible. If a master is found, the node gets joined into an already formed cluster. If no master is found, then the node itself is selected as a master (of course if the configuration allows such behavior). The process of forming a cluster and finding nodes is called discovery. The module responsible for discovery has two main purposes: electing a master and discovering new nodes within a cluster. In this section, we will discuss how we can configure and tune the discovery module.

Discovery types

By default, without installing additional plugins, Elasticsearch allows us to use Zen discovery, which provides us with unicast discovery. Unicast (http://en.wikipedia.org/wiki/Unicast) allows transmission of a single message over the network to a single host at once. Elasticsearch node sends the message to the nodes defined in...