4 LDDRIVER, SYSTEM MANAGEMENT, VAX Virtual disk driver  > The logical disk utility is a system management tool availableC to any user for controlling logical disk usage. It can also be used B for testing out things like volume shadowing, striping, host-basedI raid, or software which does dangerous things to disks without disturbing  a real disk.  F A Logical Disk is a file available on a Physical Disk, which acts as aE real Physical Disk. The Logical Disks can be created in any directory  of the Physical Disk.   G A large disk can be divided into smaller sections, each a Logical Disk, E supporting the same I/O functions as the Physical Disk. By giving the E Logical Disk File a good  protection level and mounting it private or B with device protection, you are able to add a number of protection levels to your file system.   E Logical disks may be just a single disk, part of a volumeset, part of F a stripeset, part of a host-based shadowset, part of a host-based raid set or any combination.   L The file to be used for the logical disk may be placed on any physical disk,; in any directory. A backup can be made to protect the disk.   J A physical device may be 'replaced' by a logical disk to enable logging ofK all I/O of the physical disk. In that case we don't use any container file.   K The only limitation at present is that this tool needs at least OpenVMS VAX L Version V5.5, and that it does not yet run on OpenVMS AXP. This support will be created in the future.   G The driver can be installed with VMSINSTAL. The first saveset (LD051.A) J contains the kit, while the second saveset (LD051.B) contains the sources.7 After installation full help is available with HELP LD.   , For any questions please contact the author:   	Jur van der Burg  	Digital Equipment B.V.  	Utrecht, Holland % 	Internet: vdburg@utrtsc.uto.dec.com.   