When it comes to distributed search and analytics engines, Elasticsearch was the king for years. But in 2021 the company changed its license. This change upset the open source community. Because of that Amazon Web Services (AWS) started a new project called OpenSearch. In today's time, all developers are confused about whether to stay with the original giant or embrace the community-driven fork. Here is a simple comparison of OpenSearch and Elasticsearch. The guide explains their main differences and helps you choose the right one.
The Great Split: A Brief History
Before understanding the difference, you have to understand the split. In 2021, Elastic announced the change of its software license. They dropped the open Apache 2.0 license. They adopted the SSPL and Elastic licenses. This move targeted cloud providers like AWS. Elastic wanted to stop free managed services. AWS had to pay or contribute back.
The Creation of OpenSearch: AWS rejected the new licensing terms. Red Hat, SAP and Logz.io joined AWS. They copied the final Apache 2.0 version. They used Elasticsearch version 7.10.2. They created a new copy called a fork. This new project became OpenSearch. Kibana 7.10.2 became OpenSearch Dashboards.
Since 2021, the two projects have grown independently. They now have different software features and follow separate future roadmaps and community focus.
What is Elasticsearch?
Elasticsearch is a search and analytics engine. It handles distributed data across many computers. It uses RESTful web requests to communicate. It is built on Apache Lucene software. Developed by Elastic, it is the core of the "Elastic Stack."
Pros of Elasticsearch
Elastic invests heavily in new feature development. The tool includes advanced machine learning tools. It supports vector search for AI applications. It offers threat hunting tools for security.
Data shippers called Beats work seamlessly with it. Logstash is highly optimized for this engine. The entire internal ecosystem fits together perfectly. One dedicated company backs the entire project. Users can access robust enterprise support plans.
What is OpenSearch?
OpenSearch is fully open-source software. It uses the permissive Apache 2.0 license. The community completely drives its development. It acts as a search and analytics suite. AWS heavily backs and maintains the project. A community-led model governs all decisions. No single company completely dictates the project.
Pros of OpenSearch
OpenSearch uses the permissive Apache 2.0 license. Anyone can freely use the software code. Users can modify the code without restrictions. Companies can monetize it with no fees.
Paid features from Elastic are completely free here. It includes built-in alerting tools for free. Anomaly detection features cost nothing extra. Index lifecycle management tools are fully included. Fine-grained security controls require no paid license. It is built for the AWS ecosystem. Amazon OpenSearch Service offers fully managed clusters.
Key Differences
Licensing and Cost
Elasticsearch uses a dual-licensing model. It combines SSPL and Elastic License rules. Users can run the basic tier for free. Advanced features, machine learning tools and advanced security controls demand a paid subscription. SAML authentication is locked behind a paywall.
OpenSearch software is 100% open source. It uses the Apache 2.0 license. Every single feature is free to use. Enterprise-grade security costs nothing. Alerting tools are included for free. No features are hidden behind paywalls.
Ecosystem and UI
Elasticsearch pairs directly with Kibana. Kibana acts as the visualization dashboard. The user interface is highly polished. It offers a feature-rich experience. It includes specialized observability tools. Built-in SIEM features provide robust security. It contains dedicated enterprise search tools.
OpenSearch pairs with OpenSearch Dashboards. This tool is a fork of Kibana. It resembles older versions of Kibana. The system evolved independently after the split. Development focuses heavily on core logging. Built-in alerting tools are a priority. It emphasizes community-requested plugins.
Feature Divergence
Years of separation caused codebases to drift apart. Both engines changed how they handle data internally. Both engines invest heavily in vector search technology and support generative AI applications. Both tools power Retrieval-Augmented Generation (RAG) pipelines.
Elastic added specialized endpoint security protections. The platform introduced built-in AI assistants.
OpenSearch built deep integrations with LangChain. The suite developed custom neural search plugins. It connects natively with Amazon Bedrock and SageMaker.
Hosting and Managed Services
Elastic Cloud provides the best managed experience. The managed service runs on AWS infrastructure. It is natively available on Google Cloud. Users can deploy it on Microsoft Azure.
AWS offers Amazon OpenSearch Service natively. Managed plans are available through Aiven. Instaclustr provides fully hosted cluster options. Other cloud providers offer similar hosted versions. AWS provides this service directly to users. It serves as the native cloud choice.
Which One Should You Choose?
Choose Elasticsearch if you want centralized logging, SIEM and machine learning and all the latest features. If you rely heavily on the Elastic Stack and want the most polished integration possible. If you prefer using the official Elastic Cloud and you want to avoid native cloud provider services, then you should choose Elasticsearch.
Choose OpenSearch if you require a 100% open source Apache 2.0 license and you want to build a commercial SaaS product on top of the search engine. If you want enterprise features completely for free and you need role-based access control without paying a subscription. If you are heavily invested in AWS infrastructure and want a managed experience within the AWS ecosystem, then choose OpenSearch.
