Book Image

Elasticsearch 7.0 Cookbook - Fourth Edition

By : Alberto Paro
Book Image

Elasticsearch 7.0 Cookbook - Fourth Edition

By: Alberto Paro

Overview of this book

Elasticsearch is a Lucene-based distributed search server that allows users to index and search unstructured content with petabytes of data. With this book, you'll be guided through comprehensive recipes on what's new in Elasticsearch 7, and see how to create and run complex queries and analytics. Packed with recipes on performing index mapping, aggregation, and scripting using Elasticsearch, this fourth edition of Elasticsearch Cookbook will get you acquainted with numerous solutions and quick techniques for performing both every day and uncommon tasks such as deploying Elasticsearch nodes, integrating other tools to Elasticsearch, and creating different visualizations. You will install Kibana to monitor a cluster and also extend it using a variety of plugins. Finally, you will integrate your Java, Scala, Python, and big data applications such as Apache Spark and Pig with Elasticsearch, and create efficient data applications powered by enhanced functionalities and custom plugins. By the end of this book, you will have gained in-depth knowledge of implementing Elasticsearch architecture, and you'll be able to manage, search, and store data efficiently and effectively using Elasticsearch.
Table of Contents (23 chapters)
Title Page

User Interfaces

In an Elasticsearch ecosystem, it can be immensely useful to monitor nodes and clusters in order to manage and improve their performance and state. There are several issues that can arise at the cluster level, such as the following:

  • There can be node overheads; for instance, where some nodes can have too many shards allocated and can become a bottleneck for the entire cluster
  • Node shutdown can occur due to many reasons, such as, full disks, hardware failures, and power problems
  • Shard relocation problems or corruptions, in which some shards are unable to be initialized and go online due to some issues.
  • Having very large shards can also be an issue; index performance can decrease due to large Lucene segments merging
  • Empty indices and shards waste memory and resources; however, because every shard has a lot of active threads, if there is a huge number of unused indices...