replSetMaintenance
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Definition
replSetMaintenance-
The
replSetMaintenanceadmin command enables or disables the maintenance mode for a secondary member of a replica set.
Syntax
The command has the following syntax:
db.runCommand(
{
replSetMaintenance: <boolean>
}
)
Behavior
Consider the following behavior when running the replSetMaintenance command:
- You cannot run the command on the Primary.
- You must run the command against the
admindatabase. - When enabled
replSetMaintenance: true, the member enters theRECOVERINGstate. While the secondary isRECOVERING:- The member is not accessible for read operations.
- The member continues to sync its oplog from the Primary.
- When a node receives a
replSetMaintenance: truerequest, it adds a maintenance mode task to a queue of tasks. If the queue of tasks was empty and now is not, the node will transition toRECOVERINGstate and begin to reject read requests. When a node receives areplSetMaintenance: falserequest, it removes a maintenance mode task from the queue (even if that task was initiated by a different client). If the request empties the maintenance mode task queue, the node will return toSECONDARYstate. - If you want to prevent a node from servicing reads, consider using Hidden Replica Set Members instead.