Advantages of Virtualization Software - Essay Example

Virtualization Affiliation Virtualization Introduction Virtualization is a computing concept that allows one or more operating system instances to run simultaneously on a single computer. Virtualization is a means of separating hardware from a particular operating system. Each “visitor” Operating System is managed by a Virtual Machine Monitor (VMM), which is also known as a hypervisor. Since the virtualization system sits in the middle of the guest OS and the hardware (provides an interface), it can control the use of CPU, memory, and storage by the guest, to an extent of permitting a guest OS to migrate from one machine to another (Barham et al, 2003). As such, virtualization is a technology that pools together or divides computing resources to present one or more operating environments by making use of methodologies such as hardware and software partitioning or aggregation, emulation, time-sharing, partial or complete machine simulation, and others. Virtualization technologies find key applications over a wide variety of areas such as secure computing platforms, kernel debugging and development, supporting multiple operating systems, server consolidation, and system migration thus bringing about an extensive usage (Sahoo et al, 2010). Virtualization Software VmWare VMware for desktop users usually exists in two levels, VMware Player and VMware Workstation. VMware Player is a free solution that is majorly created for casual users who need to build and run virtual machines but do not need advanced enterprise-level solutions. VMware Workstation includes all the features of VMWare Player including hardware optimization, easy virtual machine creation, driver-less guest OS printing as well as adding in the capability to replicate machines, take numerous snapshots of the guest Operating System, as well as a replay of all the changes that have been made to the guest Operating System for testing software and recording the results within the virtual machine. The latest version of VMware Workstation is VMware Workstation 11. This latest version supports the latest versions of Windows OS and Linux OS. Is also supports the latest processors and hardware, and has the capability to connect to VMware vCloud Air. Choosing VMware for an enterprise is choosing the perfect tool to increase productivity in an enterprise as well as save time. VMware Workstation consists of three components, i.e. the VMX driver , the VMM and the VMware application (VMApp). The VMX driver is normally installed within the OS so as to gain the high privilege levels that are needed by the virtual machine monitor. After execution, the VMApp loads the VMM into kernel memory. This occurs with the help of VMX driver, and gives the VMM highest privilege. At this point, the host OS only knows about the VMX driver and the VMApp, but knows not about the VMM. The machine now consists of the host world as well as the VMM world. The VMM world can initiate direct communication with the processor hardware or communicate via the VMX driver to the host world. Nonetheless, every switch to the host world requires all the hardware states to be saved and restored on return, which makes switching hit the performance. VMware products are mainly targeted towards x86-based servers and workstations. Consequently, VMware Station has to deal with the hitches that arise as x86 is not a fully-virtualizable architecture. VMware tackles this problem via a patent-pending technology that dynamically rewrites parts of the hosted machine code for the insertion traps every time VMM intervention is needed. Workstation 11 enables one to create and control policies around virtual machines and deliver applications to end-users in a Workstation 11 restricted virtual machine container. It is powerful in protecting corporate content by restricting access to Workstation virtual machine settings like copy and paste, drag and drop, and connecting USB devices. Moreover, Workstation 11 virtual machines can be encrypted and password-protected to ensure that unauthorized users are unable to tamper with the corporate virtual machines settings (vmware, 2015). Virtual machines can be shared, one of the most effective ways of sharing and testing applications within a team in a more production like environments. When VMware Workstation is run as a server, a repository of pre-loaded virtual machines is then shared in every desired configuration with teammates, department or organization. Virtual Box VirtualBox is a powerful virtualization product targeted towards x86 and AMD64/Intel64 architectures. The product is suitable for both enterprise and home use. VirtualBox is an extremely feature rich virtualization product, and is also famous for its high performance in enterprise environments It is a powerful professional solution that is available at no cost as Open Source Software. VirtualBox currently runs on Windows, Linux, Macintosh, and Operating Systems hosts. The virtualization software supports a large number of guest operating systems including Linux (2.4, 2.6 and 3.x), Windows (NT 4.0, 2000, XP, Server 2003, Vista, Windows 7, Windows 8), OpenBSD, DOS/Windows 3.x, Solaris and Open Solaris and OS/2. It also allows restricted virtualization of OS X guests on Apple hardware since version 3.2.0 was released. OSx86 can also be installed using VirtualBox. Developed by oracle, VirtualBox is being actively developed with frequent releases and an ever growing list of features, growing number of supported guest operating systems and platforms it runs on. VirtualBox may be installed on an existing host operating system. The software can create and manage guest virtual machines, each with a guest operating system as well as its own virtual environment. So as to achieve the best possible experience, guest additions should be installed on the guest operating system. It comprises of device drivers and system applications that optimize the guest operating system so as to attain better performance and usability (Li, 2010). With version 4 of VirtualBox, the core package is free software that was released under GNU General Public License version 2 (GPLv2). Non-personal use, for instance, installed many copies of the software on large number of dissimilar machines, on behalf of many different end-users by a network administrator. That type of situation would require purchasing a special volume license. Fee for software update and license support is also required per user or per socket (Oracle, 2014). A standard oracle e-business discount is normally offered on the purchase of Oracle VM support and Oracle linux (Oracle, 2014). Virtual Box has a lot of advantages. It offers GUI-based wizard for cloning a VM. It also supports multiple virtual monitors for a guest Virtual Machine (Li, 2010). Multiple virtual monitors belonging to a VM can be shown in multiple windows of host machine, or even through multiple physical monitors It can also be installed in most of the existing host OSes. Virtual Box supports multiple types of disk images such as vdi and hdd. However, Virtual BOX cannot access NATed guest Virtual Machines from host machine without allowing port forwarding on host machine. NATed guest VMs are also secluded from one other, and cannot communicate with one another. It also does not support USB 3.0 as well as nested hardware assisted virtualization (Li, 2010). Microsoft Virtual PC Microsoft’s Virtual PC was acquired from Connectix. This virtualization software is quite similar to what is offered by VMware Workstation. It is founded on the Virtual Machine Monitor (VMM) architecture and allows the user create and configure one or several virtual machines. In addition to the features supported by VMware, Virtual PC provides two differentiating functionalities. It normally maintains an undo disk that lets the user easily undo some previous operations on the hard disks of a VM. This facilitates easy data recovery by users and might be of great benefit in several circumstances. One other remarkable feature is binary translation. Virtual PC uses binary translation to provide x86 machines on Macintosh-based machines (Honeycutt, 2003). Some of the shortcomings that the Virtual PC possesses in terms of features are as follows. Compared to VMware, Linux, Solaris, FreeBSD, OpenBSD, etc are not supported as guest Operating Systems in Virtual PC. The Virtual PC VMs do not have support for Small Computer System Interface (SCSI) devices, unlike VMware workstation, even though some SCSI disks are acknowledged as IDEs by the VMs. In addition, Virtual PC does not let users add or upgrade the hardware set for a VM. Once it has been configured, it makes it impossible to alter the hardware devices a VM owns later on. Linux or thirteen other exotic operating systems are not accessible as host OS. Virtual PC supports USB and redirection. Peripherals such as flash drives and digital cameras can be connected, and one can easily print from the guest to host OS printers. Virtual PC also supports multithreading in which several virtual machines can be run concurrently. On the other hand, Virtual PC does not support drag and drop file-sharing between the host and guest OS. It also does not support the capability to commit any changes in undo disks after turning off the support (Sahoo et al, 2010). Advantages Disadvantages Computer Requirements Initial Costs Future Savings -High security -Reliability and availability -Cost reduction -Load balancing -Legacy applications -Failures are costly. -Investment in skills. -Server hardware -Storage hardware -Virtualization software -Desired CPU. -Memory -I/O -Networks: switches - OS licensing - Desired CPU -Memory -I/O -Network connectivity setup -Complete installation Virtualization platform Licensing Labor Obsolescence costs -Software licensing. -Staff time savings -Improved security -Staff headcount reduction. -Network port reduction -Reduced space costs Virtualization Advantages Enterprises using virtualization are assured of high security. Compartmentalization of environments with diverse security requirements in various virtual machines one can choose to use the guest operating system and tools that are quite appropriate for each environment (Barham et al, 2003). For instance, in the case of running the Apache web server on top of a Linux guest OS and a backend MS SQL server on top of a guest Windows XP OS, all in the same hardware platform , an attack on any of the VM does not compromise others. Virtualization also comes with reliability and availability. A software failure in a VM does not affect other virtual machines. In addition, virtualization saves cost. It is quite possible to achieve cost reductions by merging smaller servers into more powerful servers. Cost reductions stem from hardware cost reductions, operations cost reductions in terms of personnel, software licenses and floor space (Barham et al, 2003). Adaptability to workload variations is also achieved using virtualization. Changes in intensity levels of workloads can be simply taken care of by fluctuating resources and priority allocations among virtual machines. As the software state of an entire virtual machine is entirely encapsulated by the VMM, it is quite easy to migrate VMs to other platforms so as to improve performance through better load balancing (Sahoo et al, 2010). Even when an organization chooses to migrate to a dissimilar operating system, it is possible to continue to run legacy applications on the old Operating System running as a guest OS within a VM. This decreases the migration cost. Disadvantages Virtualization has its disadvantages too. Even though quite rare, the occurrence of physical failures can be devastating. For example, if the primary hard disk containing all the virtual and physical data is stolen or destroyed then all servers, both the virtual and physical ones will need to be restored. This can cost the enterprise a lot (Sahoo et al, 2010). Enterprises will require investing in training existing network administrators who do not possess the skills that are required to administer a virtual network. Errors in a virtualized system require complex troubleshooting. This will requires great expertise and experience of working and troubleshooting any virtualization problems (Sahoo et al, 2010). Costs and Future savings The savings derived from virtualization include reduced costs for software licensing, savings on staff time, less costs on security related problems, reduced staff headcount hence reduced expenditures on manpower, reduces network ports as well as a reduction on the amount paid for space (Brinkmann et al, 2004). References Barham, P., Dragovic, B., Fraser, K., Hand, S., Harris, T., Ho, A., ... & Warfield, A. (2003). Xen and the art of virtualization. ACM SIGOPS Operating Systems Review, 37(5), 164-177. Brinkmann, A., Heidebuer, M., Meyer auf der Heide, F., Rückert, U., Salzwedel, K., & Vodisek, M. (2004). V: Drive–Costs and Benefits of an Out-of-Band Storage Virtualization System. In Proceedings of the 12th NASA Goddard, 21st IEEE Conference on Mass Storage Systems and Technologies (MSST). Honeycutt, J. (2003). Microsoft Virtual PC 2004 Technical Overview. Microsoft, Nov. Li, P. (2010). Selecting and using virtualization solutions: our experiences with VMware and VirtualBox. Journal of Computing Sciences in Colleges, 25(3), 11-17. Oracle. (2014, Dec 1). Oracle VM Support. Retrieved from http://www.oracle.com/us/corporate/pricing/els-pricelist-070592.pdf Sahoo, J., Mohapatra, S., & Lath, R. (2010, April). Virtualization: A survey on concepts, taxonomy and associated security issues. In Computer and Network Technology (ICCNT), 2010 Second International Conference on (pp. 222-226). IEEE. vmware. (2015). VMware Workstation. Retrieved June 2015, from VMware: http://www.vmware.com/products/workstation Read More