AWS OPENSEARCH SERVICE
AWS has announced the successor of Amazon Elasticsearch Service (Amazon ES) or you can say rename the Amazon ES to Amazon OpenSearch Service.
WHAT IS AMAZON ELASTICSEARCH?
So, back in 2015, when Amazon Elasticsearch Service (Amazon ES) was launched, it was a fully managed service that was used
- Perform interactive log analytics,
- Real-time application monitoring,
- a website search, and more.
WHY AWS CHANGES FROM AMAZON ELASTICSEARCH TO AMAZON OPENSEARCH?
So, we need to understand why AWS renamed it or move from Elasticsearch to OpenSearch.
- The main reason is licensing. On January 21, 2021, Elastic NV(Creator company of Elasticsearch, Kibana, Beats, and Logstash.) announced that they will not release new versions after Elasticsearch version 7.10.2 and Kibana 7.10.2 under the permissive 2.0 version of the Apache License (ALv2).
- Instead, They will release Elasticsearch and Kibana under the Elastic license, with source code available under the Elastic License or Server Side Public License (SSPL), which are not open source and do not offer users the same freedom, which restricts developers to use software wherever and how they want.
- For this reason, AWS created OpenSearch, (a community-driven, open-source fork) from the latest version of Elasticsearch and Kibana & renamed Amazon Elasticsearch Service to Amazon OpenSearch Service as it now supports OpenSearch 1.0. Although the name has changed, AWS will continue to deliver the same experiences without any negative impact on ongoing operations, development, or business use.

HOW TO USE THE AMAZON OPENSEARCH SERVICE?
- It's very seamless to use Amazon Opensearch, just go to AWS Management Console.
- Search for OpenSearch in AWS Search Bar & Select Amazon OpenSearch Service
- Choose to Create a domain.
- Then in Step 1: Choose deployment type, select OpenSearch (latest), that's it, enjoy the latest feature of OpenSearch.

HOW TO UPGRADE TO THE AMAZON OPENSEARCH SERVICE?
To upgrade a domain to OpenSearch (latest),
- Choose the domain that you want to upgrade,
- Choose Actions, and then select Upgrade domain.

- Select version to upgrade to OpenSearch 1.0
- Perform the pre-upgrade checks for issues and take a snapshot of the cluster by selecting Check upgrade eligibility as the upgrade process is irreversible. It can’t be paused or canceled.

- Then, repeat the process with operation Upgrade. It takes from 15 minutes to several hours to complete.
OPENSEARCH FEATURES
REFERENCES:
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