Card Reader

[Scott Mertens]

I have a new computer I installed Linux on Red Hat Enterprise Linux ES 
release 4 (Nahant), it has one of those all-in-one card readers on it. I 
have made mountpoints as root as follows for my thumb, Compact flash and 
secure digital drive.

mkdir /mnt/thumb
mkdir /mnt/cf
mkdir /mnt/sd

Now when I tried to mount the Thumb (USB) drive I got an error # mount /dev/sda2 /mnt/thumb
mount: /dev/sda2 already mounted or /mnt/thumb busy.

So what have I done wrong?  I'm thinking sda2 is wrong, but don't know why?

df -h shows the following

[root at localhost mnt]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
                      183G  2.9G  171G   2% /
/dev/sda1              99M   19M   76M  20% /boot
none                  247M     0  247M   0% /dev/shm
[root at localhost mnt]#

Thanks.