Virtualization Products Term Paper
Virtualization, in computing refers to the creation of virtual version of storage devices, virtual computer hardware platforms and computer network resources (Sapp, 2013). This process started in 1960’s with the division of system resources with the help of mainframe computers between several applications. After that, the meaning of this term is broadened. However, virtualization helps in the integration of several services to the physical server that every server appear to work as the standalone server. The major three types of virtualization technology are OS visualization. Hardware emulation and Para virtualization. The hardware emulation is also divided to the hypervisor type 1 and hypervisor type 2.
Operating System Virtualization
Operating system visualization refers to the creation of virtualized software layer above the operating system of host which reside above the layer of hardware. In this system an operating system interferences for the running of applications and it gives the feeling of complete operating system for the applications. Every virtualized environment has its own system libraries, file system, process tables and its own network configuration. This is also known as container. So, the software emulation of the entire OS in the physical server is the OS virtualization essence. In general, the creation of abstracted view of the operating system including the process table, root file system, are the attributes of OS virualization. The products under this virtualization are Virtuozzo, Open VZ and Sun Solaris which are great for isolating the applications, training and webhosting.
Advantages and Disadvantages: The major advantage of this virtualization is that it provides the least overhead among different visualization solutions. This provide the highest density and high performance virtual environment.
However, the major disadvantage is that they support only one operating system as a base and the guest operating system is in the single server. In this case, a single operating system i.e. windows or Linux can be supported. Moreover, all the OS must have the similar version and must possess the same patch level as in case of base OS. In case of Base OS crash, the virtual container become unavailable.
In this case, a specialized software also known as hypervisor is used for the creation of hardware emulation for the operating system in a single server. This can be helpful in hosting several operating system with the single server. The operating system that is loaded to each operating machine work as the unmodified and standalone operating system. When the VM or virtual machine is running, the function of hypervisor is to the make the changes to the operating system part that makes the system calls. The Hypervisor changes the operating system with the help of entering the piece of code also known as binary translation. The binary translation takes part in four places in the operating system i.e. processor, network, memory and storage and show the interaction with the hardware. In general, it gives the inlaying hardware’s abstracting view, gives heterogeneous operating system support and it is a leading virtualization in the market. The products in this regard are VMware that utilizes the hypervisor technology for their products.
Types of Hypervisors: There are two types of hypervisor. They are classified as type 1 and type 2 hypervisor. Type 1 hypervisor also known as bare-metal implementation as they sit directly on the hardware top and there is no need of operating system because of their ability to interact directly with the hardware resources. They are also faster than the type 2 hypervisors. The products for the type 1 hypervisor are Microsoft Hyper-V, VMware ESX and Xen variants.
Type 2 hypervisor reside over the top of operating system. However, there is no direct communication with the hardware and this decreases their efficiency as compared to type 1. The type two products are VMware Player, Microsoft Virtual Server, and VMware Workstation.
Advantages and Disadvantages: The major advantage of type 1 hypervisor is that in crash of single virtual machine, the guest operating system is not get affected and it is considered more secure than the type 2 hypervisor. Because of less overhead, these hypervisors are faster than the type 1 hypervisor (Marshall, Reynolds, & McCrory, 2006).
Major advantage of type 2 hypervisor is that the operating system is responsible for all hardware and because of this the type 2 hypervisor can support an increase range of hardware. Moreover, installation of type 2 is much easier than the type 1.
The major disadvantage of the type 2 is that they have more chances of failure as if the base operating system is effected it may impact the virtual machine and guest operating system. In this case, VM will get reboot if the base OS needs the reboot.
In this type of Paravirtualization, there is no emulation of the hardware in software. In this case, the hardware coordinated or multiplexes the access to the hardware recourses in the virtual machine favor. In this type of environment a guest operating system known as DomainO is installed on the bare-metal architect directly and this contains not devices or drivers for the storage and network. However, the privileged guest operating system known as DomainO shows the direct hardware access.
When there is need to access the hardware resources, a message to DomainO that access the hardware on the guest operating system is sent. After returning the data to the hardware, DomainO read the information and send it to the guest operating system. In contrast to the hardware emulation, where the device drivers were installed in hypervisor, the drivers here are used for the DomainO (Marshall, Reynolds, & McCrory, 2006). In general, the Paravirtualization multiplexes the hardware resource access, offers high per formance, and requires the modification of guest operating system and complex than the hardware emulation. The products using the Paravirtualization are Xen open source virtualization software.
Advantages and Disadvantages: There are various advantages of the Paravirtualization. The major advantage is that in this case, they have not their own drivers. The users don’t have to depend on the hypervisor software. The other bog advantage of this virtualization is that the approach of this system is faster.
The major disadvantage of this product is the requirement for the modification of guest operating system for the execution and communication with the hypervisor. In this condition, there must be the modification of Kernal guest before the installation (“What are different types of virtualization,” n.d.).
Virtualization proved to be effective in various applications. For the development and testing of applications and system testing.
Applications of Virtualization
- Server consolidation.
- Future development and testing of applications.
- Educational training.
- Server load balancing.
- Disaster recovery.
- Server pooling.
- High availability and Failover
Marshall, D., Reynolds, W. A., & McCrory, D. (2006). Advanced Server Virtualization: VMware and Microsoft Platforms in the Virtual Data Center. CRC Press.
Sapp, K. L. (2013). Instant VMware Player for Virtualization: Packt Publishing Ltd.
What is virtualization? (n.d.). Retrieved April 25, 2019, from Opensource.com website: https://opensource.com/resources/virtualization
What are different types of virtualization. (n.d.). Retrieved April 26, 2019, from http://virtualizationtutor.com/what-are-different-types-of-virtualization/,