Mongodb – How MongoDB allocate new data block when data block is full

I had found this a while ago for the possibility of validating json data against a schema. If you wanted to do something like this, however, there's stuff you can do in javascript inside the database.

I will try to be brief. Most of the answers are documented.

Q1: There are many ways. Shard a collection using _id:hashed and set initial number of chunks 2 and then start inserting documents (100 is a good number of docs). You will see documents on both shards.

Q2: It uses range partitioning. Each shard holds ranges of the shard key.

Q3: Sharding is an automated process, all you need to do is to determine a shard key.

Q4: Stop the balancer, backup shard rs1, rs2 and the config server, start the balancer.

Q5: On a sharded cluster the access point should be the mongos