How to turn on Archivelog Mode

Database Version            : 11gR2 StandAlone

OS                                          : Linux 5

1.       Shutdown the database in immediate mode. If the database is shutdown in abort mode, then start the database and shutdown again in immediate mode.

SQL> select name, open_mode from v$database;

NAME      OPEN_MODE

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

ORCL      READ WRITE

SQL> archive log list;

Database log mode              No Archive Mode

Automatic archival             Disabled

Archive destination            USE_DB_RECOVERY_FILE_DEST

Oldest online log sequence     23

Current log sequence           25

SQL>

SQL> shutdown immediate;

Database closed.

Database dismounted.

ORACLE instance shut down.

SQL>

2.       Start the database in mount mode.

SQL> startup mount;

ORACLE instance started.

Total System Global Area  313860096 bytes

Fixed Size                  1336232 bytes

Variable Size             255855704 bytes

Database Buffers           50331648 bytes

Redo Buffers                6336512 bytes

Database mounted.

SQL>

3.       Turn on the archivelog mode for the database.

SQL> alter database archivelog;

Database altered.

SQL>

4.       Open the database.

SQL> alter database open;

Database altered.

SQL>

5.       Check that the database is running on archive log mode.

SQL> select name, open_mode from v$database;

NAME      OPEN_MODE

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

ORCL      READ WRITE

SQL> archive log list;

Database log mode              Archive Mode

Automatic archival             Enabled

Archive destination            USE_DB_RECOVERY_FILE_DEST

Oldest online log sequence     23

Next log sequence to archive   25

Current log sequence           25

SQL>

Done!!