MongoDB Documentation, Release 3.0.4 Name Description flushRouterConfig Forces an update to the cluster metadata cached by a mongos . addShard Adds a shard to a sharded cluster . cleanupOrphaned Removes orphaned data with shard key values outside of the ranges of the chunks owned by a shard. checkShardingIndex Internal command that validates index on shard key. enableSharding Enables sharding on a specific database. listShards Returns a list of configured shards. removeShard Starts the process of removing a shard from a sharded cluster. getShardMap Internal command that reports on the state of a sharded cluster. getShardVersion Internal command that returns the config server version. mergeChunks Provides the ability to combine chunks on a single shard. setShardVersion Internal command to sets the config server version. shardCollection Enables the sharding functionality for a collection, allowing the collection to be sharded. shardingState Reports whether the mongod is a member of a sharded cluster. unsetSharding Internal command that affects connections between instances in a MongoDB deployment. split Creates a new chunk . splitChunk Internal command to split chunk. Instead use the methods sh.splitFind() and sh.splitAt() . splitVector Internal command that determines split points. medianKey Deprecated internal command. See splitVector . moveChunk Internal command that migrates chunks between shards. movePrimary Reassigns the primary shard when removing a shard from a sharded cluster. isdbgrid Verifies that a process is a mongos . 10.4.3 Reference Documentation Config Database 10.4. Sharding Reference 737 show collections You can return a list of the collections, with the following helper: To access the config database, connect to a mongos instance in a sharded cluster, and use the following helper: use config Warning: Modification of the config database on a functioning system may lead to instability or inconsistent data sets. If you must modify the config database, use mongodump to create a full backup of the config database. Important: Consider the schema of the config database internal and may change between releases of MongoDB. The config database is not a dependable API, and users should not write data to the config database in the course of normal operation or maintenance. The config database supports sharded cluster operation. See the Sharding (page 661) section of this manual for full documentation of sharded clusters. Config Database (page 737) Complete documentation of the content of the local database that MongoDB uses to store sharded cluster metadata.