Oracle : Ошибка ORA-38857

"cannot mark redo thread %s as enabled"
*Cause: The standby switchover or failover operation failed because it
needs to mark a redo thread as enabled. However, the control file
was recreated with a MAXINSTANCES value smaller than the thread
number of the redo thread.
*Action: Recreate the control file with a larger MAXINSTANCES value.

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