Oracle : Ошибка ORA-16817

16817, 0000, "unsynchronized fast-start failover configuration"
*Cause: The fast-start failover target standby database was not
synchronized with the primary database. As a result, a fast-start
failover could not happen automatically in case of a primary
database failure.
*Action: Ensure that the fast-start failover target standby database is
running and that the primary database can ship redo data to it.
When the standby database has received all of the redo data from
the primary database, the primary and standby databases will then
be synchronized. The Data Guard configuration may then fail over
automatically to the standby database in the event of loss of the
primary database.

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