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  • Definition
  • Behavior
sh.startBalancer(timeout, interval)

Changed in version 4.2.

Starts the balancer in a sharded cluster. Starting in MongoDB 4.2, sh.startBalancer() also enables auto-splitting for the sharded cluster.


mongosh Method

This page documents a mongosh method. This is not the documentation for database commands or language-specific drivers, such as Node.js.

For the database command, see the balancerStart command.

For MongoDB API drivers, refer to the language-specific MongoDB driver documentation.

For the legacy mongo shell documentation, refer to the documentation for the corresponding MongoDB Server release:

mongo shell v4.4

The method can take the following options:


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.


Optional. The frequency (in milliseconds) at which to check if a balancing round has started.

Changed in version 3.4: Only applicable when using version 3.4 mongo shell with earlier version sharded clusters.s

You can only run sh.startBalancer() on a mongos instance. sh.startBalancer() errors if run on mongod instance.

Starting in MongoDB 3.4, the mongo shell method sh.startBalancer() is a wrapper around the balancerStart command. As such, the method does not wait for balancing to start.

In earlier versions, the method waited for the balancing to start.


← sh.splitFind()

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