I have migrated my existing data in 4 nodes Cassandra (with RF=3) to Elassandra and after putting my mappings whole data got indexed into Elassandra. After the completion of indexing, all nodes show a consistent result in /_cat/indices?v API. But as soon as I restart any node the data on that node is reduced substantially, index size as well as the number of records. If I restart another node of the cluster the problem shift to that node and previous node recovers automatically. For more details and detailed use case please refer to the issue I have created with Elassandra.
Upgrade to Elassandra v6.8.4.3 has resolved the problem. Thanks!