Covert database noarchive mode to archive mode

Covert database noarchive mode to archive mode

1-SQL> archive log list
Database log mode             No Archive Mode
Automatic archival             Enabled
Archive destination            /oracle/product/10.2.0/db_1/dbs/arch
Oldest online log sequence     2
Next log sequence to archive   3
Current log sequence           3

2.Shutdown the database
SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.

3. startup mount
SQL> startup mount
ORACLE instance started.

Total System Global Area 1073741824 bytes
Fixed Size                  2089400 bytes
Variable Size             264244808 bytes
Database Buffers          801112064 bytes
Redo Buffers                6295552 bytes
Database mounted.

4- SQL> alter database archivelog;

Database altered.

5- shutdown the database
SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.

6-startup
SQL> startup
ORACLE instance started.

Total System Global Area 1073741824 bytes
Fixed Size                  2089400 bytes
Variable Size             264244808 bytes
Database Buffers          801112064 bytes
Redo Buffers                6295552 bytes
Database mounted.
Database opened.

7- Now verify
archive log list
SQL> archive log list;
Database log mode               Archive Mode
Automatic archival             Disabled
Archive destination            /oracle/product/10.2.0/db_1/dbs/arch
Oldest online log sequence     2
Current log sequence           3