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

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

In a Prod database, flashback database was on and someone deleted a flashback log file.

so first I tried to off the flashback option then tried to open the database but it was reporting this error.  then figured out that we had few restore points (guaranteed restore point) created before.

So solution came after dropping those restore points and then tried to open.  you can see in below -

Database was in MOUNT mode.

SQL> conn / as sysdba
Connected.

SQL> alter database open;
  
*
ERROR at line 1:
ORA-38760: This database instance failed to turn on flashback database


SQL> alter database flashback off ;

Database altered.

SQL>
SQL> alter database open ;
alter database open
*
ERROR at line 1:
ORA-38760: This database instance failed to turn on flashback database


SQL> select name from v$restore_point;

NAME

--------------------------------------------------------------------------------

PRE_SWITCHOVER_PRODCDB

PRE_SO_PRODCDB_20181207

SQL> drop restore point PRE_SWITCHOVER_PRODCDB;

Restore point dropped.

SQL> drop restore point PRE_SO_PRODCDB_20181207;

Restore point dropped.

SQL> alter database open ;

Database altered.

SQL> select status from v$instance;

STATUS

------------

OPEN

SQL> alter pluggable database all open;

Pluggable database altered.