how to rebalance mongodb after adding a shard

How do I rebalance mongodb data after adding 开发者_开发问答a new shard

I do not think it does it automatically?

I could not find anything, it's there support for this?

Also the key for my shards is unique

Thanks,

When you add a new shard, MongoDB should automatically start re-balancing data according to your shard key.

However, it will not start re-balancing until there is a certain amount of data. So if you don't have few gigs of data, you probably won't see any re-balancing.

If you have lots of data and you add a shard and it never starts migrating data, then it's time to go to the google group and start asking questions. As it stands, lots of people are using auto-sharding and it is definitely re-balancing automatically.

I'm not saying you haven't found a bug, just that you'll need a lot more data to back that up.