The version of ES is 7.0.0. I am curious to know how index stored at ES nodes. Let me give you one scenario:
In our ES cluster, there are 5 indices including .kibana. The _cat/shards api has been showing that data of only two indices reside on IP A. The role of A is mdi (master, data, ingest eligible node). But when I am going to /app/elasticsearch/data/ESNode/nodes/0/indices directory in IP A, there are five folders. The name of each folder corresponds to uuid of those five indices. According to me, as _cat/shards has been showing that data of only two indices reside on IP A, there should be only two folders in /app/elasticsearch/data/ESNode/nodes/0/indices. Please let me know if I am missing out something.
Thanks for your time,