ORA-38760: This database instance failed to turn on flashback database, ora-38760flashback

ORA-38760: This database instance failed to turn on flashback database, ora-38760flashback
ORA-38760: This database instance failed to turn on flashback database

Problem Background:
Test the database to execute shutdown immediate, the log reports an error, the error message is: ORA-19815: WARNING: db_recovery_file_dest_size of 4322230272 bytes is 99.77% used, and has 9814016 remaining bytes available.
Then I execute startup force mount to force the database off and start to the mount state, delete historical backup and archive information through RMAN and then start the database to report an error ORA-38760.

Symptom:

SQL> startup mount;ORACLE instance started.Total System Global Area 2872786944 bytesFixed Size                  2256712 bytesVariable Size            2634023096 bytesDatabase Buffers          218103808 bytesRedo Buffers               18403328 bytesDatabase mounted.SQL> alter database open;alter database open*ERROR at line 1:ORA-38760: This database instance failed to turn on flashback database

Problem Analysis:
This error is returned after you view Metalink because the Flash back information is incomplete.

[oracle@db01 ~]$ oerr or 38760oerr: Unknown facility 'or'[oracle@db01 ~]$ oerr ora 3876038760, 00000, "This database instance failed to turn on flashback database"// *Cause: Database flashback is on but this instance failed to//         start generating flashback data. Look in alert log for more//         specific errors.// *Action: Correct the error or turn off database flashback.

Solution:

#1. Disable flash backup and then open databaseSQL> alter database flashback off; SQL> alter database open; #2. Another method is to directly shut down the database and then start the SQL> startup force mount; ORACLE instance started. total System Global Area 2872786944 bytesFixed Size 2256712 bytesVariable Size 2634023096 bytesDatabase Buffers 218103808 bytesRedo Buffers 18403328 bytesDatabase mounted. SQL> alter database open; Database altered. SQL>

Oracle enabling flashback can fail, error message: ORA-00439: failed to start the work can: Flashback Database;

Flashback database requires that the database be in archive mode, and you must use resetlogs to open the database after the flash.
Check whether the database archive mode and flash back are enabled
SQL> select log_mode, open_mode, flashback_on from v $ database;

LOG_MODE OPEN_MODE FLASHBACK_ON
----------------------------------------
Archivelog read write no -- FLASHBACK_ON is NO, which indicates that the flash back feature is not enabled.