I am using elastic-search 5.3. I wanted to upgrade it to the latest ES version say 7.7. Which is the best way to upgrade from 5.3 to 7.X with the minimum number of downtime or minimum time required?
I have a cluster of 11 nodes including 3 master nodes and 8 data nodes. My index data size is approx. 1.8 TB. I am using the Elastic-Search mapping type also. I read that after 5.6 or later, ES removed the concept of mapping type. If I reindex data with the API of ES, will it be taken care of all the things, or I should add something extra?
I have seen a couple of articles for upgrading but did not conclude on that. So can anyone help me with this?