Shut down the database from sqlplus or server manager. Backup all
files to secondary storage (eg. tapes). Ensure that you backup all data
files, all control files and all log files. When completed, restart your
database.
Do the following queries to get a list of all files that needs to be backed
up:
select name from sys.v_$datafile;
select member from sys.v_$logfile;
select name from sys.v_$controlfile;
Sometimes Oracle takes forever to shutdown with the "immediate"
option. As workaround to this problem, shutdown using these
commands:
alter system checkpoint;
shutdown abort
startup restrict
shutdown immediate
Note that if you database is in ARCHIVELOG mode, one can still use
archived log files to roll forward from an off-line backup. If you cannot
take your database down for a cold (off-line) backup at a convenient
time, switch your database into ARCHIVELOG mode and perform hot
(on-line) backups.