Virtualization of IT resources
Virtualization of IT resources has become a popular the past few years but has been around in some form for many years. Example; thirty years ago IBM had virtual operating systems that allowed multiple copies of an operating system to run simultaneously on mainframe computers. Virtualization is the use of hardware and software to create environments that are perceived as one or more different entities. Example; virtualization can make one server appear as many different machines. Virtualization can create an appearance of multiple instances of Operating Systems (OS)’s, network resources, and storage that are actually being run from a single physical machine. Virtualization is method that converts physical IT resources into virtual resources.
Server Virtualization
Server virtualization makes one server appear as many different servers. Virtual servers can support multiple OS’s of the same or different type. Virtual servers make use of a software layer called a hypervisor. OS’s are installed on the hypervisor software layer instead of directly on the physical hardware. The hypervisor manages each OS’s system execution and resources. Virtual servers provide the following benefits for businesses; they consume less power, have a smaller physical footprint, generate less heat costing less to cool, and they are easier to install and configure. Virtual servers also use physical resources more efficiently particularly CPU utilization. Load balancing and scaling allow virtual servers to be created as loads increase. In contrast when loads are lighter computing resources can be used for other operations reducing waste. Microsoft Hyper-V for example allows an organization to create and manage a virtualized computing environment by using virtualization technology that is built in to Windows Server. Hyper-V allows an organization to establish or expand cloud services, better utilize hardware, improve business continuity, establish or expand a virtual desktop infrastructure (VDI), and use virtual machines to reproduce different computing environments without the need for acquiring or maintaining all the hardware you would otherwise need.
Storage Virtualization
Data virtualization separates physical data storage from logical presentation that users and applications can see. It hides the physical details of the actual storage device. Virtual storage can span many different drives and devices through the use of logical drives which provide the usable space that users and application can see and use. Virtual storage allows businesses to scale storage demand as needed, pay only for resources they need and as they go, transparent backup and data replication, support most common OS’s, users can access storage from most devices anywhere they have a network or internet connection, and it allows for easy file and folder sharing. Example; Dropbox provides software that creates a local virtual drive which will synchronize with cloud storage. This model allows users and application to interact with what appears to be a standard file folder. This type of virtualization provides business users a way to access their files from the Dropbox drive from any device that has an internet connection, automatically replicates their data for protection, and provides a way for users to share files and collaborate with others.
Network Virtualization
Physical networks can be segmented into logical networks such as Virtual Local Area Networks (VLAN), and Virtual Private Networks (VPN). VLANS and VPN’s allow users a way to connect to resources remotely through the creation of a logical secure network. Example; with this model a remote user can connect to datacenter resources remotely through the internet using a VPN connection. The connection itself is created across the internet, host, and user networks, but to the user and the hosted resource, it appears that they are connected via a Local Area Network (LAN). VPN’s allow organizations a way to establish secure encrypted communications between remote users and resources, simplify communications protocols which lowers costs, scalability, and provide a method for remote employees to access company resources securely and reliably. VLANS allow organizations to segment their physical networks into logical networks. Example, computers in the business office of an organizations connected together on a separate VLAN. VLAN’s benefit organizations by increasing network performance, simplify network management, and simplify and increase network security. The ability to create VPN’s and VLAN’s is limited to network equipment capable of creating virtual network environments. Example, Cisco offers and extensive line of enterprise networking equipment capable of creating virtual networks for customers that range from small home and office users, to large scale data centers.
Power Virtualization
Virtual Uninterruptible Power Supplies (UPS) allow organization supply power where it is needed, and reduce or power down equipment that is not in use. In combination with UPS management software, organizations can use virtual UPS to automatically scale up or down, or redirect power to mechanisms such as virtual machines as they are created or shut down. Virtual UPS solutions such as Critical Power are designed to work with most major VM vendor applications.
Virtual Desktops
Desktop virtualization is a way to run multiple OS’s at the same time on the same machine. This has several advantages to an organization to include; the ability to run, and switch between, separate OS’s quickly, the ability to run different type OS’s from the same machine, eliminates the need for duplicate hardware, and reduces power consumption. An example of how this can benefit an organization would be a software tester. Running test applications inside virtual desktops eliminates the need to switch between physical machines. Another type of virtual desktop is Virtual Desktop Infrastructure (VDI). VDI allows a computer to pull its OS from the network when it powers up. The benefits of VDI to a business include; multiple users can use the same OS image. This reduces OS administration since updates only need to be applied to a few images instead of several separate machines. Users can choose different OS’s to use for different purposes, example, use Windows 7 for general use, but switch to Windows XP to use a legacy application that will not run in Windows 7. Reduced hardware cost since much of the storage and computing requirements are handled by the OS server. Reduce the need to troubleshoot diverse problems associated with several physical machines. Example, an OS problem can be trouble shot and corrected at the server or in the image instead of having to perform the same operation on every machine in the facility.
Summary
The following are general advantages and disadvantages of virtualization:
Advantages;
- Increased device utilization, particularly CPU utilization.
- Decreased physical device footprint.
- Decreased power consumption.
- Simplified OS and application administration.
- Simplified provisioning and patch management.
- Ease of scalability.
- Increased user access to resources.
- Better flexibility in managing multiple different OS’s.
- More efficient management of software licenses.
- Better utilization reporting leading to better capacity planning.
- Improved disaster recovery and business continuity.
Disadvantages;
- Additional staff training may be required to understand the use of virtualization technology.
- Some applications are not well suited for virtualization. Some applications require specific hardware or drivers.
- Virtualization adds overhead to computing resources making some applications slower.
- Applications that depend on advanced graphics such as 3D modeling software, the required drivers can slow applications noticeably.
References
Brooke, B. (2014, December 31). What is VPN (virtual private network) and what are its advantages and disadvantages? Retrieved July 20, 2016, from https://www.quora.com/What-is-VPN-virtual-private-network-and-what-are-its-advantages-and-disadvantages.
Cisco Products. (n.d.). Cisco Products and Services. Retrieved July 20, 2016, from http://www.cisco.com/c/en_in/products/index.html.
Critical Power. (n.d.). Virtualization and UPS Power Management. Retrieved July 20, 2016, from http://www.criticalpowersupplies.co.uk/virtualization-virtual-power-management.
Dropbox Sharing. (n.d.). Sharing files and folders. Retrieved July 20, 2016, from https://www.dropbox.com/help/topics/sharing_files_and_folders.
Harbaugh, L. (2012, March 22). The Pros and Cons of Using Virtual Desktop Infrastructure. Retrieved July 20, 2016, from http://www.pcworld.com/article/252314/the_pros_and_cons_of_using_virtual_desktop_infrastructure.html.
Mahaney, B. (n.d.). VLAN – Benefits and Limitations. Retrieved July 20, 2016, from http://www.people.eku.edu/mahaneyb/CISStudentClub/1007/index.htm.
TechNet Hyper-V Overview. (2016, May 31). Hyper-V Overview. Retrieved July 20, 2016, from https://technet.microsoft.com/library/hh831531.aspx.
