Assessment
The goal of Migration Assistant is to streamline the process of migrating from one location or version of Elasticsearch/OpenSearch to another. However, completing a migration sometimes requires resolving client compatibility issues before they can communicate directly with the target cluster.
Understanding breaking changes
Before performing any upgrade or migration, you should review any breaking changes that might exist between versions because there may be changes required in order for clients to connect to the new cluster. Use the following tool by selecting the versions in your migration path. The tool will respond with any breaking changes you should note when migrating:
Find a list of breaking changes for your migration path
Impact of data transformations
Any time you apply a transformation to your data, such as changing index names, modifying field names or field mappings, or splitting indexes with type mappings, these changes might need to be reflected in your client configurations. For example, if your clients are reliant on specific index or field names, you must ensure that their queries are updated accordingly.
We recommend running production-like queries against the target cluster before switching over actual production traffic. This helps verify that the client can communicate with the target cluster, locate the necessary indexes and fields, and retrieve the expected results.
For complex migrations involving multiple transformations or breaking changes, we highly recommend performing a trial migration with representative, non-production data (such as in a staging environment) to fully test client compatibility with the target cluster.
Supported transformations
The following is a list of transformations that are included in Migration Assistant. They can be enabled, combined, and configured to customize a migration for your use case. Depending on your use case and the type of transformation, a transformation may have to be added to Capture-and-Replay, Metadata Migration Tool, or Reindex-from-Snapshot. To request additional Migration Assistant transformations, create a GitHub issue in the OpenSearch migrations repository.