■ IntroduCtIon
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provide actionable insights. Detailed coverage is given to production-related aspects and
scaling the stack.
How Is the Book Organized?
Chapter 1 emphasizes the importance of log analysis in today’s big data-crazy
world. It analyzes the challenges with log analysis. It presents the ELK stack as a thorough
solution for log analysis. Different components of the ELK stack (Elasticsearch, Logstash,
and Kibana) are introduced with a description of their functions and installation.
Chapter 2 gets you started with using Logstash for log generation, collection, and
filtering. It begins with introducing the configuration settings of Logstash. It then goes on
to illustrate how Logstash facilitates shipping of logs, filtering, and transforming any type
of data to a common format. This can further help in arriving at actionable insights.
Chapter 3 throws light on the internal organization of Logstash and its plugins.
Logstash has a diverse collection of input, filter, codec, and output plugins. An overview
of the common plugins is provided. It then shows you how to create and use your own
custom plugin.
Chapter 4 introduces data management using Elasticsearch. This chapter shows
how to add data, index it, update it, and delete it. It goes on to show how to work with
distributed document stores.
Chapter 5 explores the elaborate mechanism for searching for data available in
Elasticsearch. It also illustrates Query DSL and filters.
Chapter 6 examines how Elasticsearch maps data. It then goes on to show how to
map data for relevant analysis.
Chapter 7 explores the subject of aggregates. It provides a top-level view of the entire
set of documents. This is unlike queries, which just focus on a particular document. It
also covers grouping of documents into buckets.
Chapter 8 introduces Kibana. It explains basic concepts and key features.
Chapter 9 shows how to work with Kibana by illustrating its interface to filter
and visualize log messages gathered by Elasticsearch. It covers the main interface
components, and demonstrates how to create searches, visualizations, and dashboards.
Chapter 10 covers the last piece in the Kibana armor: the dashboard. Various
visualizations can be combined to give a holistic view using a dashboard. This serves as a
single area for visualizing and analyzing data in real time.
Chapter 11 provides guidance on scaling the ELK cluster. This enhances the
capability to handle more data, index many more datasets, and search data faster. In
these days of cloud computing and NoSQL databases, scaling is very important because
there are situations when it is required to process millions or even billions of documents.
It’s not always possible to support this kind of load with one instance of Elasticsearch.
Chapter 12 addresses the key aspects of running the ELK stack in a production
environment. Monitoring the different components and troubleshooting any problem is
quite important. Custom configurations are required for specific scenarios.
Chapter 13 highlights some of the real life stories of how the ELK stack is being used
for a diverse set of scenarios. The ELK stack has transcended from the realm of lab trials
to live multinode clusters. These success stories should encourage you to experiment
with the ELK stack for your data storage and search needs.
Who Should Read This Book?
This book is for anybody who is dealing with data. The ELK stack can help in
solving existing problems and open the way to new features that have yet to be rolled
in. This book is for beginners and experienced users alike. While the beginners will get