OpenSearch vs. Elasticsearch: Search Without Vendor Lock-in
Enterprise search is business-critical today - and this is where you don't want to risk unexpected restrictions or dependencies on individual providers. But that's exactly what happened when Elastic changed the license for Elasticsearch in 2021. The software was suddenly no longer free to use without restrictions, which startled many companies.
Some feared a vendor lock-in, as Elastic tied certain functions to proprietary licenses. As a result, many looked for alternatives. OpenSearch, an AWS-initiated fork of Elasticsearch, came on the scene and remains 100% open source under Apache 2.0 license - with nearly identical functionality, but no usage restrictions or hidden costs.
In this article, we take a detailed look at how this situation came about, what the current status is and why OpenSearch may in many cases be the better choice for digital sovereignty and control over company data.
Table of Contents
- License Change at Elastic: How the Problem Arose
- OpenSearch as an Open Source Alternative Without Restrictions
- Community and Governance: Linux Foundation Takes Over
- Current Status: Elastic Rows Back and Performance Comparisons
- When is OpenSearch the Better Choice?
- When Does Something Speak for Elasticsearch?
- Our Services for Your Search Infrastructure
- Conclusion: Digital Sovereignty Through OpenSearch
- Contact Us
- Further Links and Sources
License Change at Elastic: How the Problem Arose
Elasticsearch once started as an open source project under Apache 2.0 license and formed the core of the popular ELK stack (Elasticsearch, Logstash, Kibana). But in January 2021, Elastic incurred the displeasure of the community: Elasticsearch and Kibana were switched to a dual license - Server Side Public License (SSPL) and the specially created Elastic License v2 (ELv2).
Neither of these licenses was recognized by the Open Source Initiative (OSI), which effectively meant that Elasticsearch was no longer "free" open source software. Elastic justified this move as a defense against cloud providers such as Amazon Web Services (AWS), which offered Elasticsearch as a service without contributing to the project.
The Consequences for the Community
The effects of this license change were far-reaching:
- Many in the user and developer community felt offended
- Previously freely available functions were suddenly subject to proprietary restrictions
- Companies were faced with uncertainty regarding future usage rights
- Potential costs and requirements were unclear
This uncertainty led to alternatives coming into focus. Large cloud providers in particular reacted promptly: AWS announced in 2021 that it would fork the last free Elasticsearch version (7.10.2) in order to provide an open alternative. From this fork emerged OpenSearch - an independent project that continues the original open course.
OpenSearch as an Open Source Alternative Without Restrictions
OpenSearch was created by AWS together with partners to maintain the vision of a truly open enterprise search solution. All OpenSearch code is released under the Apache License 2.0, giving users maximum freedom.
What Does This Mean in Concrete Terms?
Companies can use, modify, extend, embed, monetize or offer OpenSearch as part of their own services as they wish - without the risk of breaking the license. This permissive license ensures that there is no vendor lock-in. Unlike Elastic's proprietary add-ons, there are no hidden barriers or fees.
Range of Functions: Drop-in Replacement for Elasticsearch
Functionally, OpenSearch offers an almost identical experience to Elasticsearch 7.10.2 - including the search engine itself and a visualization dashboard (OpenSearch Dashboards, analogous to Kibana). For many use cases it is a drop-in replacement, i.e. existing Elasticsearch setups can be converted to OpenSearch with minimal customization.
Cost Savings Through Integrated Features
The cost savings are particularly attractive: OpenSearch already includes numerous features out-of-the-box that were part of the paid X-Pack with Elastic. For example, extended security functions such as fine-grained access management and audit logging are integrated free of charge. Companies therefore save the license fees that would have been incurred for comparable functions in the Elastic world.
High-end features such as alerting, index lifecycle management or anomaly detection were also provided as open modules in the OpenSearch project - functions that Elastic customers previously only received for an additional charge. Although proprietary components (e.g. certain X-Pack modules and telemetry) had to be removed from the original code and replaced with open source alternatives, the OpenSearch team was quick to provide replacements. The result is a platform that offers all the functionality of the previous open source Elastic version, plus some enhancements from the community.
Community and Governance: Linux Foundation Takes Over
Another advantage is the active open source community behind OpenSearch. Although the project is initiated by AWS, it is explicitly community-driven.
In 2024, AWS even handed over governance to the Linux Foundation and founded the OpenSearch Foundation. This move underscores the commitment to independent development and increases trust among organizations that want to avoid any vendor lock-in.
A lively community of developers and companies is working on OpenSearch - new features and improvements are constantly being introduced. Although even AWS admits that the development of some cutting-edge functions (such as in the area of AI/vector search) has lagged somewhat behind proprietary Elastic development, the gap is constantly shrinking. OpenSearch, for example, has now integrated artificial intelligence for anomaly detection and is experimenting with vector search to keep pace with current trends.
Current Status: Elastic Rows Back and Performance Comparisons
The dynamics in this license war did not remain one-sided. Elastic, for its part, reacted to the migration trend: three and a half years after the controversial license change, it took the step back to the open source world in late summer 2024.
Elasticsearch Returns to Open Source - With Restrictions
Elastic announced that Elasticsearch and Kibana will once again be provided under an OSI-recognized open source license - specifically the GNU AGPLv3. This move was perceived as a surprising turnaround. Elastic emphasized that it had "never stopped acting like an open source community", but conceded that an OSI-compliant license would finally dispel any doubts.
In fact, AGPL v3 is a stricter copyleft license aimed at forcing cloud providers to release modifications should the code be offered as a service.
What Does This Mean for Users?
For existing Elastic users, the new license option means that you can theoretically use Elasticsearch in pure open source mode again, but many advanced features will remain reserved for paying customers. Elastic now offers a free open source version with basic functions under AGPL, while important extensions such as machine learning, special security features or certain integrations are still only available in the higher, proprietary subscription tiers.
In other words, the source code is open again, but on the functional side, Elastic is still trying to attract customers to its own platform for premium features.
In the meantime, Elastic and AWS are maintaining a pragmatic coexistence according to their own statements - Elastic even speaks of a "strong partnership" with Amazon. Whether this appeasement will be enough to win back the trust of the open source community remains to be seen. Industry observers note that many users are not so quick to restore trust once it has been burned.
In addition, although AGPL is open source, it is less attractive to some companies than a permissive Apache license due to the viral clauses (obligation to pass on changes in SaaS operation). OpenSearch therefore retains a strategic advantage here for all those who want maximum freedom with the code.
Performance and Innovation
Performance and innovation are other aspects in which the two projects continually measure themselves. Elastic has invested heavily in the further development of its stack and published benchmark tests that show Elasticsearch to be 40-140% faster than OpenSearch in some cases - with lower resource consumption.
Our research and external analyses indicate that Elastic actually has a performance advantage, especially with very large amounts of data or complex queries.
But: OpenSearch certainly holds its own for average application scenarios. In many medium-sized use cases (e.g. typical log analytics or internal searches), most users will not notice a dramatic difference. The OpenSearch community is also working on further increasing efficiency.
Interestingly, Elastic itself argues that its customers could achieve a high return on investment (ROI) with the stack and save costs through more efficient storage - statements that should, of course, be viewed from a marketing perspective and depend on many factors in real-life scenarios.
When is OpenSearch the Better Choice?
For IT decision-makers, the question arises as to which system is more advantageous at the end of the day. There is no general answer to this - it depends on the priorities of the company in question.
Nevertheless, there is a clear trend in favor of OpenSearch when the following factors are in the foreground:
1. Digital Sovereignty and Control Over Data
OpenSearch under Apache 2.0 license gives you full control. You can run the software anywhere - on-premise or in any cloud - and retain sovereignty over your data and code.
There is no manufacturer who dictates how you can use the system or who can unilaterally change the conditions. This independence is particularly attractive for:
- Industries with strict compliance requirements
- Government institutions
- Companies that want to avoid vendor lock-in
2. Cost Savings
OpenSearch is completely free to use - even extended features do not incur any license fees. You save the expense of Elastic subscriptions (e.g. the previously required X-Pack fees for security, alerting, machine learning, etc.), as comparable functionality is included in OpenSearch at no extra charge.
The cost savings can be considerable, especially for large cluster installations.
3. No Functional Restrictions in Core Use
For most "standard" applications, OpenSearch offers everything that Elasticsearch does:
- ✅ Indexing
- ✅ Powerful full-text search
- ✅ Aggregations
- ✅ Kibana-like dashboards (OpenSearch Dashboards)
- ✅ Distributed scaling
- ✅ RESTful API
- ✅ Plugin ecosystem
The basic search and analysis requirements can be met without compromises. Special newer Elastic functions (such as special ML modules, Elastic Workplace Search integrations or maps) are still missing in some cases, but these are not relevant in every use case. There are also often alternative open source solutions that can be added if required.
4. Active Further Development and Community Support
OpenSearch has the backing of a growing community and major players (above all AWS). The OpenSearch Foundation under the umbrella of the Linux Foundation ensures that development is managed openly and collaboratively.
- Several companies contribute code
- Regular releases
- Open plugin ecosystem
- Active forums and GitHub discussions
- Improved documentation
The project is lively and future-proof - an important signal for decision-makers who rely on the longevity of a platform.
When Does Something Speak for Elasticsearch?
To be fair, it must be mentioned: Elasticsearch can play to its strengths if you are willing to (partially) commit to Elastic as a provider and pay for premium features.
If you are looking for the highest performance on an extreme scale, the most comprehensive feature list and dedicated enterprise support, Elastic offers a well-rounded overall package - but then you have to accept the license conditions and potential dependency.
Our Services for Your Search Infrastructure
WZ-IT supports you in the implementation of your enterprise search solution - whether OpenSearch or Elasticsearch:
Consulting and Conception
- Analysis of your search and analytics requirements
- Evaluation: OpenSearch vs. Elasticsearch
- Architecture design for scalability
- Migration strategy for existing systems
Installation and Setup
- On-premise in your data center
- Private cloud on dedicated servers
- Hybrid solutions according to your requirements
- Cluster setup with high availability
- Integration into existing IT infrastructure (LDAP, SSO, etc.)
Operation and Maintenance
- 24/7 monitoring
- Automatic backups
- Security updates
- Performance tuning & optimization
- Index management & lifecycle policies
- SLA with guaranteed availability
Conclusion: Digital Sovereignty Through OpenSearch
Ultimately, OpenSearch provides a welcome freedom of choice in the world of enterprise search. In times when control over one's own data and the avoidance of lock-in are becoming increasingly important, OpenSearch gives companies an option to rely on state-of-the-art search technology without handing over the keys.
OpenSearch scores over Elasticsearch particularly in terms of digital sovereignty - i.e. self-determined control over software and data. Whenever independence, cost control and open licensing have higher priority than the last bit of proprietary additional functionality, OpenSearch is the better choice for your search and analytics ecosystem.
The resulting competitive situation ultimately also has positive effects: It forces both projects to develop further. For users, this means innovation and choice, from which they can select the optimal solution for their needs - free from gagging contracts and with a good feeling of control over their own data infrastructure.
"Digital sovereignty is not a luxury, but a necessity for modern companies."
Contact Us
Would you like to migrate from Elasticsearch to OpenSearch or set up a new search infrastructure? We will be happy to advise you on the right solutions.
Book your free and non-binding initial consultation with us here: Make an appointment.
You can also reach us by phone on +49 2922 875068 or by e-mail at [email protected]. We look forward to hearing from you!
Further Links and Sources
- Best Elasticsearch alternatives in 2025 for your use case - Algolia
- Elastic Returns to Open Source: Will the Community Follow? - InfoQ
- Elasticsearch erscheint wieder als Open-Source-Software - heise online
- Elastic Search and Open Search - a brief history of the license war - DEV Community
- OpenSearch vs. Elasticsearch - SHI GmbH
- Elasticsearch vs OpenSearch in 2025: What the Fork? - Pureinsights
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