About the migration process

The process of migrating from Elasticsearch OSS to OpenSearch varies depending on your current version of Elasticsearch OSS, installation type, tolerance for downtime, and cost-sensitivity. Rather than concrete steps to cover every situation, we have general guidance for the process.

Three approaches exist:

• Use a snapshot to migrate your Elasticsearch OSS data to a new OpenSearch cluster. This method may incur downtime.
• Perform a restart upgrade or a rolling upgrade on your existing nodes. A restart upgrade involves upgrading the entire cluster and restarting it, whereas a rolling upgrade requires upgrading and restarting nodes in the cluster one by one.
• Replace existing Elasticsearch OSS nodes with new OpenSearch nodes. Node replacement is most popular when upgrading Docker clusters.

Regardless of your approach, to safeguard against data loss, we recommend that you take a snapshot of all indexes prior to any migration.

If your existing clients include a version check, such as recent versions of Logstash OSS and Filebeat OSS, check compatibility before upgrading.

For more information about OpenSearch migration tools, see OpenSearch upgrade, migration, and comparison tools.

Upgrading from Open Distro

For steps to upgrade from Open Distro to OpenSearch, refer to the blog post How To: Upgrade from Open Distro to OpenSearch.