For scheduled operation to work properly, you need to have the crond(8) - demon running. Also the at(1) program needs to be available and a suitable entry be in your crontab(1) file. This should be the case on any properly installed system, so do not worry about it unless you get error messages.
By setting the commands to execute by MULTIBUF , you can even support automatically changing tapes if your hardware supports this. 7.1