MongoDB Sharding: data is saving in primary shard only

Question

I have implemented sharding for two collections based on a column which is not indexed. Now after checking sh.status(), I can see all the data is saving in primary shard only. Data is not distributing among the other shard servers. What to do?

Answer 1

As written in mongodb docs "To shard a collection, you need to select a shard key. A shard key is either an indexed field or an indexed compound field that exists in every document in the collection. MongoDB divides the shard key values into chunks and distributes the chunks evenly across the shards. To divide the shard key values into chunks, MongoDB uses either range based partitioning or hash based partitioning" you can't solve your problem without indexing it. so create an indexed field first then check status of sh.status() .
Reference: https://docs.mongodb.com/manual/reference/method/sh.status/ &
https://docs.mongodb.com/manual/core/sharding-introduction/