By default, Elasticsearch creates five primary shards and a copy of each primary shard when you create an index. These copies are called replicas. So, the replica shard is simply a copy of a primary shard. Replica shards are used to improve the search performance and failover. If a node crashes in a way, Elasticsearch uses one of the available replica shards of the node to avoid any data loss. For this reason, a replica of a primary shard will not be allocated in the same node with the primary shard. Hence, choosing the right amount of shards and replicas is very important. Unlike primary shards, replicas can be added and removed at any time. The number of primary shards must be specified before creating an index.
Elasticsearch Indexing
By :
Elasticsearch Indexing
By:
Overview of this book
Beginning with an overview of the way ElasticSearch stores data, you’ll begin to extend your knowledge to tackle indexing and mapping, and learn how to configure ElasticSearch to meet your users’ needs. You’ll then find out how to use analysis and analyzers for greater intelligence in how you organize and pull up search results – to guarantee that every search query is met with the relevant results! You’ll explore the anatomy of an ElasticSearch cluster, and learn how to set up configurations that give you optimum availability as well as scalability. Once you’ve learned how these elements work, you’ll find real-world solutions to help you improve indexing performance, as well as tips and guidance on safety so you can back up and restore data. Once you’ve learned each component outlined throughout, you will be confident that you can help to deliver an improved search experience – exactly what modern users demand and expect.
Table of Contents (15 chapters)
Elasticsearch Indexing
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Free Chapter
Introduction to Efficient Indexing
What is an Elasticsearch Index
Basic Concepts of Mapping
Analysis and Analyzers
Anatomy of an Elasticsearch Cluster
Improving Indexing Performance
Snapshot and Restore
Improving the User Search Experience
Index
Customer Reviews