Our team are thinking of using redisearch on top Elasticsearch as a store unit for real time data. When looking at the document: https://oss.redislabs.com/redisearch/Administration/ I see: RediSearch will not work correctly on a cluster. Does it mean in order to use redisearch, we have to use the commercial version and cant build redisearch cluster by ourself? Thanks
RediSearch will "agree" to work on a cluster setup, but that will not help you much. Creating a clustered search engine requires an additional coordination layer. Right now that's available only for the commercial version - or you can opt to write one on your own! :)
(Disclosure: I'm the original author of RediSearch, although I do not work for Redis Labs nor contribute to the project anymore).