Is rrf available in the free, self-hosted version of elastic search?

Elastic Stack Elasticsearch
1

I am using Elasticsearch as self-hosted in docker container, 8.9.1.
When I query with the parameter rrf Reciprocal rank fusion, I get this message elasticsearch.AuthorizationException: AuthorizationException(403, 'security_exception', 'current license is non-compliant for [Reciprocal Rank Fusion (RRF)]')
Do I understand correctly that this function is not available in free plan ? I couldn't find any information about it anywhere

2

Have a look at: Subscriptions | Elastic Stack Products & Support | Elastic