[Users] Cannot configure storage

Hello all I'm booting oVirt node from USB and want to use my hard drive for storing VMs and stuff. When I have booted the node from USB I try to mount the hard drive into a folder in the file-system but I am getting the following error. mount: /dev/sda1 is already mounted or /mnt busy Anyone who knows about this error? Regards Nauman Abbas Assistant System Administrator (LMS), Room No. A-207, SEECS, National University of Sciences & Technology, + 92 321 5359946