Virtual Hard Drives (VHD) Research Paper Example | Topics and Well Written Essays - 1000 words

Virtual Hard Drives (VHD) - Research Paper Example Yet another type is the differencing one, which can be attached to any of the two other types, for increasing the performance of the system. The fixed sized disks do not have to specify for the minimum space required on the computer file system of the host, as it can automatically acquire the required space. On the other hand, dynamically expanding VHDs will take up the required space, according to their need. (Rouse) Virtual Hard Disk drives are the best alternative, when conducting cost-effective operations on computer systems. Using VHD, diverse operating systems can be loaded on the same PC, which allows the host to run different software programs on the same computer, while allowing the software developers to test their programs in a cost-effective manner. During February, 2013 Microsoft purchased the Virtual Hard Disk software from Connectix Virtual PC Software, which was originally responsible for creation of this software. Thereafter, Microsoft renamed this product as Microso ft Virtual PC. (VHD) Virtual Hard disk Formats Apart from the fixed and dynamic formats, as mentioned above, there is another format of VHD called ‘Differencing’ type. Each format can perform different tasks, as they vary in performance. Fixed size VHD The space required by this type of VHD is allocated on the physical Hard disk storage, while creating the VHD. While the fixed size can be increased, in an offline operation, the software does not support reducing the size. The fixed size characteristic of this type ensures optimum efficiency in operation of the system. However, due to the commitment of space allocated, it cannot be used by the physical drive, incase the VHD does not utilize any portion of the given space. Dynamically expanding VHD This file format counters the disadvantage of the fixed type VHD, as the space utilized by dynamically expanding VHD will depend on the actual requirement for the data size that is being written to it. However, ‘on-disk m eta-data’ size will add to this requirement. The file size can vary from as small as 43 KB in a VHD of this type to 20GB. The choices of optimization of performance are available with this type of VHD. However, the performance can be slower, for read or write functions, than the fixed size type VHDs. Differencing VHD This type of VHD can be associated with either of the above two types. While they can implement many additional features to their parent VHD, they also are responsible for prevention of any changes to the parent hard drive. The advantage of using this type is that space taken from physical hard drive can be reclaimed by compacting a differencing VHD.(Ranjana1) Native VHD boot Native boot VHD configuration is available in Windows 7 and Windows server 2008 R2. This allows the user to use the VHD as the computer running operating system without requirement of any parent system or hypervisor. In addition, Native boot provides full access to all the files in the PC sy stem, as the virtual volumes are visible, after the VHD portions are automatically attached to the system. Native VHD boot supports all the tree types of VHDs. However, the system will fail in case the expanding VHD requires more than the space available with the physical host drive. Only BIOS-based and UEFI-based firmware supports Native VHD boot. (Frequently Asked Questions) VHD vs. VHDX Windows Server 2012 has made available another VHD format, called VHDX. It has many advantages. The main