KNoppix newbie

I regularly mount a couple of nfs shares. In my previous system I just added them to fstab and could mount them at will.

The question is why does fstab get generated at every boot ?
Assuming there is a good reason, the next question is how can I add my own mount points and have them added to fstab during the generation process?

If it gets re-generated to detect usb storage devices, can I just add mountpoints for those and then add "nofstab" to my boot parameters ?

thanks


--A