basically, in the shell script would be something like this, name it like /home/user/backup.sh
#!/bin/sh
rsync -a /from/this/path /to/this/backup/dir
save and close, see rsync's man page for more options.
then you need to add a cron job:
# crontab -e
and you would want to have an entry like this
* * * * 0 /home/user/backup.sh
# --^----
# \every Sunday
save and close and that should be it.
also see here http://www.adminschoice.com/docs/crontab.htm or cron's manpage for the syntax and usage of c
ron, it can be confusing
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