Firstly, Knoppix has root login turned off, but this does not mean you cannot act as root. The command to use is "sudo' which will give you full root access, from within your user account. You will need to type sudo before each command you need root access for. You can also get by this and get full root access by typing "sudo su" which will use sudo, to bypass the password request coming from the "su" command.
As far as mounting your SATA drives. fstab is basically a script of mount commands. When you add a drive in there it will cause it to mount automatically on boot. You can manually do this by using the mount command. Also, instead of restarting after changing the fstab file, use "mount -a" which will reprocess the fstab file for you.
Good luck
Tom
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