How Do I Disable the Balancer?

Procedure

1. Log in to a database through mongo shell.
2. Run the following command in the command window of the mongos node to switch to the config database:

   use config

3. Run the following commands to check whether the balancer can be disabled:

   while( sh.isBalancerRunning() ) {      
             print("waiting...");           
             sleep(1000);
   }

   • If the command output is waiting, the balancer is migrating chunks. In this case, do not disable the balancer. Otherwise, data inconsistency may occur.
     Figure 1 Viewing the command output
     
   • If no command output is displayed, the balancer is not migrating any chunks. In this case, you can disable the balancer:

4. Disable the balancer.
   • If you migrate the entire DB instance, run the following command to disable the balancer.

     sh.stopBalancer()

   • If you need to disable the balancer of the sharded collections to be migrated, run the following command:

     sh.disableBalancing("database.collection")

     database.collection indicates the namespace of the collection to be migrated.