First make sure you aren't currently in the /mnt/cdrom directory via a shell or graphical file manager.
Try: "umount /mnt/cdrom"
If that doesn't work try that or "eject cdrom" as root. Hopefully that should work.
I`ve typed:
mount /dev/cdrom /mnt/cdrom
Now I want to put another disk and I don`t know how to unmount it?
Tried eject and umount but it gives me device busy.
First make sure you aren't currently in the /mnt/cdrom directory via a shell or graphical file manager.
Try: "umount /mnt/cdrom"
If that doesn't work try that or "eject cdrom" as root. Hopefully that should work.
I have gotten in the habit of doing this:
sudo umount -a
It won't umount anything that's in use (/home, /, /proc etc) but it will umount everything it can.

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