Cheatcode for Knoppix DVD(Klaus Knopper sez .Knoppix26 toram

While attempting to load a Knoppix Live DVD (remastered 2.181GB) using cheatcode ...toram... the boot messages report :

/bin/cp writing'/cdrom2/KNOPPIX/knoppix': no space left on device

This statement is repeated for all elements on the DVD disc (readme, gif,FAQ (languages, etc)

Is the toram cheatcode valid for DVD entry into ram.?

Does the ramdisk size require a change?

My system has 2.5GB of ram. The DVD operates correctly ..fromhd., but does not boot ...fromhd toram, nor toram.