You can enable fast start failover to fail over automatically when the primary database becomes unavailable.

DGMGRL> SWITCHOVER to ‘pc00sby1’;
DGMGRL> FAILOVER to ‘pc00sby1’ [IMMEDIATE]; If immediate is used then no attempt is made to apply any unapplied redo that has been received.

Reinstating databases.
Must have flashback on and flashback logs available.

start the db in mount mode.
DGMGRL> REINSTATE DATABASE ‘pc00prmy’;

if reinstate fails then recreate from a backup / copy
and then enable:
DGMGRL> ENABLE DATABASE pc00prmy;