Is there a way to unmount anyway?
 

It keeps saying that the device is busy, but that's because I need to install a program that takes 3 cd's. Can I force unmount? Or use a program or something...so I can switch cd's?

You could say

fuser -km /mnt/cdrom

but I doubt that is what you wanted to do.

So the answer to your question is that yes you can force unmount, but by doing that you kill the process which is using the CD drive, and you just said you didn't want to do that.

Can't you copy all the files to the hard drive in advance?

TIM

You could try this...

• Copy all the CDs to your harddrive, but as ISO files:
• $ dd if=/dev/cdrom of=Programme.CD1.iso
• Mount the first ISO file onto the cdrom mountpoint:
• # mount -o loop Programme.CD1.iso /mnt/cdrom
• Run your programme.
• When it asks for the next CD, don't umount the dir, just mount the 2nd disc over the top:
• # mount -o loop Programme.CD2.iso /mnt/cdrom
• Continue with your programme.
• Do the same for CD3.
• When you're done, and you are back to the terminal, you need to umount each of them:
• # umount -d /mnt/cdrom
  # umount -d /mnt/cdrom
  # umount -d /mnt/cdrom
• And that should be it!