A note about licensing
The core components of the stack are open source software projects, licensed under a mix of the Apache 2, Elastic License version 2 (ELv2), and Server Side Public License (SSPL) licensing agreements. The LICENSE.txt file in the root of each product's GitHub repository should explain how the code is licensed.
A paid license is not required to learn about and explore the Elastic Stack features covered in this book. A trial license can be activated for full access to all the features for a limited period upon installing the software.
To focus on learning about the features and technical aspects of the product, there will be no notes on licensing implications after this section. Please refer to the Elastic Subscriptions page to understand what kind of license you might need for a production deployment of the technology:
