The process of upgrading from Elasticsearch OSS (including Open Distro for Elasticsearch) to OpenSearch varies depending on your current version of Elasticsearch OSS, install 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]({{site.url}}{{site.baseurl}}/upgrade-to/snapshot-migrate/) to a new OpenSearch cluster.
- Perform a [rolling upgrade or cluster restart upgrade]({{site.url}}{{site.baseurl}}/upgrade-to/upgrade-to/) on your existing nodes.
- Replace existing Elasticsearch OSS nodes with new OpenSearch nodes. Node replacement is most popular when upgrading [Docker clusters]({{site.url}}{{site.baseurl}}/upgrade-to/docker-upgrade-to/).
Regardless of your approach, to safeguard against data loss, we recommend that you take a [snapshot]({{site.url}}{{site.baseurl}}/opensearch/snapshot-restore/) of all indices prior to any migration.
If your existing clients include a version check, such as recent versions of Logstash OSS and Filebeat OSS, [check compatibility]({{site.url}}{{site.baseurl}}/clients/agents-and-ingestion-tools/index/) before upgrading.
