The following table shows the compatibility of Gerrit Code Review with Elasticsearch.

Elasticsearch Version Minimum Gerrit Version Notes
2.4.x 2.14.8 or 2.15.3 Support discontinued in 2.15.8 and 2.16.1
5.6.x 2.14.8 or 2.15.3  
6.2.x 2.14.8 or 2.15.3  
6.3.x 2.14.10 or 2.15.3  
6.4.x 2.14.12 or 2.15.4  
6.5.x 2.15.8 or 2.16.1  
6.6.x 2.15.10 or 2.16.5  
6.7.x 2.15.13 or 2.16.8  
7.0.x 2.15.13 or 2.16.8 See note below about upgrades

Indices created in Elasticsearch 5.x or earlier will need to be reindexed with Elasticsearch 6.x in order to be readable by Elasticsearch 7.x. See breaking changes in Elasticsearch 7.0 for details.