Reindex legacy backing indices Technical preview; Added in 8.18.0

POST /_migration/reindex

Reindex all legacy backing indices for a data stream. This operation occurs in a persistent task. The persistent task ID is returned immediately and the reindexing work is completed in that task.

application/json

Body Required

  • mode string Required

    Value is upgrade.

  • source object Required
    Hide source attribute Show source attribute object
    • index string Required

Responses

  • 200 application/json
    Hide response attribute Show response attribute object
    • acknowledged boolean Required

      For a successful response, this value is always true. On failure, an exception is returned instead.
POST /_migration/reindex 
POST _migration/reindex
{
    "source": {
        "index": "my-data-stream"
    },
    "mode": "upgrade"
}
curl \
 --request POST 'http://api.example.com/_migration/reindex' \
 --header "Content-Type: application/json" \
 --data '"{\n    \"source\": {\n        \"index\": \"my-data-stream\"\n    },\n    \"mode\": \"upgrade\"\n}"'
Request example
An example body for a `POST _migration/reindex` request. 
{
    "source": {
        "index": "my-data-stream"
    },
    "mode": "upgrade"
}

Documentation preview

This is a preview of your version @2025-06-09 which is not yet released.

View current documentation