Book Image

Elasticsearch Essentials

Book Image

Elasticsearch Essentials

Overview of this book

With constantly evolving and growing datasets, organizations have the need to find actionable insights for their business. ElasticSearch, which is the world's most advanced search and analytics engine, brings the ability to make massive amounts of data usable in a matter of milliseconds. It not only gives you the power to build blazing fast search solutions over a massive amount of data, but can also serve as a NoSQL data store. This guide will take you on a tour to become a competent developer quickly with a solid knowledge level and understanding of the ElasticSearch core concepts. Starting from the beginning, this book will cover these core concepts, setting up ElasticSearch and various plugins, working with analyzers, and creating mappings. This book provides complete coverage of working with ElasticSearch using Python and performing CRUD operations and aggregation-based analytics, handling document relationships in the NoSQL world, working with geospatial data, and taking data backups. Finally, we’ll show you how to set up and scale ElasticSearch clusters in production environments as well as providing some best practices.
Table of Contents (18 chapters)
Elasticsearch Essentials
Credits
About the Author
Acknowledgments
About the Reviewer
www.PacktPub.com
Preface
Index

Upgrading Elasticsearch version


An Elasticsearch cluster can be upgraded to a higher version in two ways:

  • Rolling upgrade: This requires one node to stop at once and perform the upgradation.

  • Full cluster restart: This requires a complete cluster shutdown before proceeding with the upgrade task.

You need to go through the following URL for more information on the supported versions to choose the type of upgrade you need to perform:

https://www.elastic.co/guide/en/elasticsearch/reference/current/setup-upgrade.html

In both cases, to upgrade a node, the following are the easiest steps to upgrade a version node by node:

  1. Disable the routing allocation, as discussed in the previous section.

  2. Stop the node.

  3. Take a backup of the data.

  4. Take a backup of the configuration files.

  5. Remove Elasticsearch (you can simply purge it to complete the uninstallation of Elasticsearch from the server by running this command: sudo apt-get purge Elasticsearch)

  6. Install Elasticsearch with the latest release.

  7. Change the configuration...