Cause: The database either crashed or was shutdown with the ABORT
option. Media recovery cannot be enabled because the online
logs may not be sufficient to recover the current datafiles.
Action: Open the database and then enter the SHUTDOWN command with the
NORMAL or IMMEDIATE option.
Related posts
ORA-00348 Single-process redo failure. Must abort instance
ORA-00332 Archived log is too small – may be incompletely archived
Oracle Database Internal Mechanism 