MongoDB Documentation, Release 3.0.4 10.4 Sharding Reference 10.4.1 Sharding Methods in the mongo Shell 10.4.2 Sharding Database Commands The following database commands support sharded clusters . 736 Chapter 10. Sharding Name Description sh._adminCommand() Runs a database command against the admin database, like db.runCommand() , but can confirm that it is issued against a mongos . sh.getBalancerLockDetails() Reports on the active balancer lock, if it exists. sh._checkFullName() Tests a namespace to determine if its well formed. sh._checkMongos() Tests to see if the mongo shell is connected to a mongos instance. sh._lastMigration() Reports on the last chunk migration. sh.addShard() Adds a shard to a sharded cluster. sh.addShardTag() Associates a shard with a tag, to support tag aware sharding (page 682). sh.addTagRange() Associates range of shard keys with a shard tag, to support tag aware sharding (page 682). sh.removeTagRange() Removes an association between a range shard keys and a shard tag. Use to manage tag aware sharding (page 682). sh.disableBalancing() Disable balancing on a single collection in a sharded database. Does not affect balancing of other collections in a sharded cluster. sh.enableBalancing() Activates the sharded collection balancer process if previously disabled using sh.disableBalancing() . sh.enableSharding() Enables sharding on a specific database. sh.getBalancerHost() Returns the name of a mongos that’s responsible for the balancer process. sh.getBalancerState() Returns a boolean to report if the balancer is currently enabled. sh.help() Returns help text for the sh methods. sh.isBalancerRunning() Returns a boolean to report if the balancer process is currently migrating chunks. sh.moveChunk() Migrates a chunk in a sharded cluster . sh.removeShardTag() Removes the association between a shard and a shard tag. sh.setBalancerState() Enables or disables the balancer which migrates chunks between shards . sh.shardCollection() Enables sharding for a collection. sh.splitAt() Divides an existing chunk into two chunks using a specific value of the shard key as the dividing point. sh.splitFind() Divides an existing chunk that contains a document matching a query into two approximately equal chunks. sh.startBalancer() Enables the balancer and waits for balancing to start. sh.status() Reports on the status of a sharded cluster , as db.printShardingStatus() . sh.stopBalancer() Disables the balancer and waits for any in progress balancing rounds to complete. sh.waitForBalancer() Internal. Waits for the balancer state to change. sh.waitForBalancerOff() Internal. Waits until the balancer stops running. sh.waitForDLock() Internal. Waits for a specified distributed sharded cluster lock. sh.waitForPingChange() Internal. Waits for a change in ping state from one of the mongos in the sharded cluster.