ORACLE

Enabling ARCHIVELOG Mode

SQL> SELECT LOG_MODE FROM SYS.V$DATABASE;

LOG_MODE
------------
NOARCHIVELOG

Edit the pfile in either $ORACLE_BASE/admin/SID/pfile
or $ORACLE_HOME/admin/SID/pfile

############################
# Archive Log Destinations -benr(10/15/04)
############################
log_archive_dest_1='location=/u02/oradata/cuddle/archive'
log_archive_start=TRUE

You can specify as many as 10 diffrent archive log destinations
by using the paramters log_archive_dest_1 through log_archive_dest_10.
Remember, if you run out of space in your archive log destination the
database will shut down!  

SQL> startup mount

SQL> alter database archivelog;

SQL> alter database open;


To view the archive log location

SQL> select name from v$archived_log;

NAME
--------------------------------------------------------------------------------
/u01/app/oracle/dbs/arch1_8_676141561.dbf

Also , you can use.
ALTER SYSTEM SET log_archive_dest_1='LOCATION=';