The lsblk (list blocks) command can be used to list every hard drive and solid state drive connected to the computer in Linux. If Linux is a virtual machine running on top of a hypervisor such as VMWare or a virtual machine manager such as Oracle's VirtualBox, some of the hard drives and solid state drives connected to the computer may not show when running the lsblk command in Linux, because the hypervisor or virtual machine manager may not be configured to map the some of the hard drives and solid state drives to the Linux virtual machine. A hypervisor or virtual machine manager does not allow you to attach an already existing filesystem on a drive to a virtual machine. A hypervisor or virtual machine manager will only be able to create a new, empty virtual filesystem.