Today, we are happy to announce the release of Elasticsearch 2.0.0-rc1, based on Lucene 5.2.1. Elasticsearch 2.0 is feature frozen. This is the last planned release candidate before 2.0.0 GA.
IMPORTANT: This is a release candidate and is intended for testing purposes only. Elasticsearch 2.0.0-rc1 is not compatible with 2.0.0-beta1 or 2.0.0-beta2, and there is no guarantee that it will be compatible with Elasticsearch 2.0.0 GA.
DO NOT DEPLOY IN PRODUCTION
You can read the blog post about Elasticsearch 2.0.0-rc1 here.