Oracle has some examples in the documentation : http://docs.oracle.com/cd/E11882_01/backup.112/e10642/rcmbckba.htm#i1005689
If you aren't trained on Oracle Backup and Recovery scripting and setup, you MUST get yourself trained. An organisation large enough to be running AIX servers should be large enough to train DBAs.
Hemant K Chitale
there are many ways to do that:
2. cron job if using Linux/Unix
3. Task Manager if using windows
the following sample script in linux:
rman target / << EOF
backup database plus archivelog all;
backup current controlfile;
and in the crontab you can define the following to take a backup everyday at 2am:
00 2 * * * /<script_path>/backup.sh
this is just a sample, you can customize it based on your requirements and your environment.