Oracle : Ошибка ORA-16658

16658, 0000, "unobserved fast-start failover configuration"
*Cause: The fast-start failover configuration was currently unobserved
so failover was disallowed.
*Action: Make sure the observer is running and has connectivity to both
the primary and the target standby databases. Otherwise, disable
fast-start failover to perform a failover in the absence of the
observer process.

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