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Definition

balancerStart

New in version 3.4.

Starts the balancer thread. The command does not wait for a balancing round to start. You can only issue the balancerStart against the admin database on a mongos instance.

The command takes the following form:

copy

db.adminCommand( { balancerStart: 1, maxTimeMS: <number> } )

Field	Type	Description
balancerStart	any	Any value.
maxTimeMS	integer	Optional. Time limit for enabling the balancer. Defaults to 60000 milliseconds. Changed in version 3.4: If using the 3.4 mongo shell with earlier version sharded clusters, the parameter specifies the amount of time to wait for the balancing round to start.

Example

To start the balancer thread, connect to a mongos instance and issue the following command:

db.adminCommand( { balancerStart: 1 } )