Server virtualization has immensely influenced and benefitted the IT world. It has been gaining popularity year after year and its adoption is increasing every day, especially when it comes to enterprise environments. With Hypervisor server virtualization, you become capable of running different operating systems having distinct applications on an individual physical server. This way, every user on the server gets the possibility to acquire the support of dedicated resources with their virtual machines on a single server. Further, server virtualization also helps in reducing the needed number of physical servers and saving time in identifying the issues.
But, what actually has made virtualization possible are the hypervisors. The hypervisors had been designed in 1956, specifically to operate IBM RPQ for the IBM 360/65. They were created in order to test sharing systems among VMs (virtual machines). They helped in getting insights into new hardware concepts without imperiling the central production unit. However, the use of Hypervisor has extended to assign physical hardware resources to virtual units of the host machine. Moreover, they are employed for numerous other tasks incorporating cloud computing, running programs, server management, etc.
In this article, you will acquire insightful details on the hypervisor. You will get to comprehend how it is highly effective in handling the system’s performance, security monitoring, and network & hardware optimization. Let us begin with highlighting what is a hypervisor and how is it used.
What is a Hypervisor?
A hypervisor can be defined as hardware, software, or firmware that can build virtual machines and further, manage and assign resources to them. It enables you to abstract the guest machines as well as their separated operating systems from the physical hardware. This is how the hypervisor accommodates virtualization technology and facilitates the physical host machine to run multiple virtual machines (VMs) on a single system.
Moreover, these virtual machines function as guests and help in optimizing the utilization of computing resources, such as disk space, memory, network bandwidth, and others. So, it will not be wrong to say that virtualization is indistinguishably bound to hypervisor technology. And for a fact, the hypervisors were also recognized as Virtual Machine Monitors (VMMs).
The machine on which you install a hypervisor is called the host machine. And the ones that run on top of it are known as guest virtual machines. A hypervisor forms a layer between the virtual machines (guest machines) and the hardware (the physical host machine), which then controls every transaction between them. While seeing from a virtual machine’s standpoint, you will find no difference between the physical and virtualized environment. All the guest machines will not feel as if they are built or running in a virtual environment. Also, they will not get to experience that they are actually sharing available computing power. Virtual machines are dependent on the stable operation of hardware that powers them as they run with the hardware.
In order to ensure that your hypervisor is set up correctly as well as working properly, you can make use of a third-party monitoring tool such as Virtualization Manager. This tool helps in providing a full picture of the performance of your virtual machine (VM). Keeping assurance of apt performance of your hypervisor is essential for having effective virtual machines running effectively, resource use management, and device security maintenance.
Different Types of Hypervisor
There are basically two different types of hypervisor you can find – Type 1 Hypervisor and Type 2 Hypervisor. Plunge to the subsequent columns to know more about them.
What is a Type1 Hypervisor?
The Type 1 Hypervisor is also recognized by the name “bare-metal” or “native” hypervisor. This implies that this hypervisor operates straight on the physical hardware of the host machine. You do not have to load an underlying operating system prior to making type 1 hypervisor work. Since the type 1 hypervisor gets direct access to the underlying hardware, it renders effective performing and robust computing. Some common examples of Type 1 hypervisors are Microsoft Hyper-V, Citrix/Xen Server, and VMware ESXi.
Along with knowing for the most efficient and high performing, these hypervisors are also recognized to be most secure. The reason behind this is the unavailability of the defects and vulnerabilities with the Type 1 hypervisors, which are endemic to Operating Systems. Since the underlying operating system is dropped with the type 1 hypervisor, every virtual machine gets isolated. Consequently, this same separation protects them against malicious activities or security threats.
What is a Type 2 Hypervisor?
The Type 2 Hypervisor is also recognized by the name “Hosted Hypervisors.” The fundamental difference between Type 1 hypervisor and Type 2 hypervisor is that the latter is basically installed on an existing OS. This is where the name “hosted hypervisors” comes from. The type 2 hypervisor depends on the operating system of the host machine in order to undertake specific operations such as handling calls to the CPU, managing network resources, controlling memory and storage, etc. This enables type 2 hypervisors to support an extensive range of hardware. Some common examples of type 2 hypervisors are Oracle Solaris Zones, Microsoft Virtual PC, VMware Fusion, Oracle Virtual Box, VMware Workstation, and Oracle VM Server for x86.
If we talk about the origin of Type 2 Hypervisors, it will take you back to the times of x86 virtualization. At those times, the existing systems employed pre-existing operating systems while the hypervisor was used to deploy as an advanced software layer.
What is the difference between a type 1 and type 2 hypervisor?
Let us highlight a few more differences between Type 1 and Type 2 hypervisors apart from what you have learned in the previous section.
The Type 1 hypervisors need support from hardware acceleration software. They cannot operate without the availability of this hardware technology. Hardware acceleration technologies enable hypervisors to run and manage the intensive tasks needed to handle the virtual resources of the system.
The Type 2 hypervisors also make use of hardware acceleration technologies only if such features are available. However, they do not need these technologies. If the hardware acceleration technologies support is not available, the type 2 hypervisors utilize the software emulation on the physical host system.
The Type 1 hypervisors vendors are available in a considerable number. You can acquire trial periods with many of them in order to test out their services before you actually purchase them. Moreover, the licensing costs can be expensive in case you need all the bells and whistles the vendors have on offer.
Similar to the case of Type 1 hypervisors, you can have numerous vendors and products with Type 2 hypervisors as well. However, you can discover that many type 2 hypervisors are available free of cost in their fundamental versions and render satisfactory functionalities. With some of them, you can also acquire advanced features and performance boosts free of cost after installing add-on packages.
Hypervisors have been in the IT industry for a long time now. Moreover, with the increased usage of cloud computing, their significance is becoming more obvious. While you can find both the hypervisors type 1 and type 2 quite similar, the utilization of the underlying operating system marks the difference and introduces a certain amount of latency. You get this latency with the type 2 hypervisor because all the tasks and operations of its virtual machine need to go through the host operating system.
Mostly, people make use of Type 1 Hypervisors in production. However, you can find few IT environments that benefit from Type 2 Hypervisors instead. The reason for utilizing the Type 1 Hypervisor in production is the low overhead that comes with it. On the other side, the Type 2 Hypervisor serves as an ideal option for home labs and a few other test environments due to its low cost and ease of installation.
The sellers of Hypervisors will offer you various plans that can include multiple products with different licensing agreements. You must research the choices thoroughly to make the apt decision for your necessities. This is because migrating between the hypervisors later will become a tedious job as well as expensive for you. Thus, it is always better to go with the apt choice from the beginning only.