elasticsearch.ElasticsearchException: Invalid or missing tagline (OpenSearch)

Question

After migrating to AWS OpenSearch from Elasticsearch we get the following error when calling OpenSearch via the Elasticsearch-Rest-High-Level-Client:

elasticsearch.ElasticsearchException: Invalid or missing tagline [The OpenSearch Project: https://opensearch.org/]

Answer 1

As it turns out the version of the Elasticsearch-Rest-High-Level-Client was too new. We used the client version 7.15.0 with OpenSearch 1.0. We downgraded the client to 7.10.2 and it worked again.

Also using the OpenSearch-Rest-High-Level-Client in version 1.0 worked, too.