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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.
This page documents a
mongoshmethod. This is not the documentation for database commands or language-specific drivers, such as Node.js.
For the database command, see the
For MongoDB API drivers, refer to the language-specific MongoDB driver documentation.
For the legacy
mongoshell documentation, refer to the documentation for the corresponding MongoDB Server release:
The method can take the following options:ParameterTypeDescription
Optional. Time limit for enabling the balancer.
Defaults to 60000 milliseconds.
Changed in version 3.4: If using the 3.4
mongoshell 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
mongoshell with earlier version sharded clusters.s
You can only run
sh.startBalancer()errors if run on
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.