Introduction of Hypervisor in Cloud Computing
The software that helps in the creation of Virtual machines where a virtual platform is provided to the operating systems to manage and execute the virtual machines is called Hypervisor which is otherwise called Virtual Machine Monitor or Emulator or Virtualizer. Hypervisor term describes how it manages all the operating systems and supervises the same and hence we can call hypervisor as supervisor of supervisors as operating systems manages the working of each applications working on the same. One system can control various virtual machines and this helps to manage the working of virtual machines via hypervisor.
Working of Hypervisor in Cloud Computing
Working of hypervisor is given below:
- We have a host computer in which one or more virtual machines are created. These virtual machines are created on top of the hypervisor. The job of the hypervisor is to manage virtual machines created on the host computer. Virtual machines will not have any connection with the host computer and all the jobs are done by themselves with the help of hypervisors.
- Hypervisors can be software or hardware type. When the hypervisors manage the virtual machines, we call hypervisors parallel desktops and it acts as an intermediate between hosts and virtual machines. VMware Player is also a software hypervisor kind. Now, hardware hypervisors are those that do not have any operating systems and work directly with host systems. Microsoft hypervisors and Citrix XenServer are examples of hardware hypervisors.
- Controlling the data flow into the virtual machines is managed by Hypervisor. Data flow and networking into virtual machines is looked upon and stored in the data center. Also, hypervisor act as a storage center where the data is stored virtually. Hence, physical storage is not expected for virtual machines. A storage pool is created where we can store any amount of data coming from virtual machines.
- When we use more than one virtual machine in the host system, it is not necessary that the operating systems of all virtual machines are the same. It can be either Windows, Linux, CentOS, or Mac. This increases the burden of the host system and here Hypervisor plays a major role in making the virtual machines independent. The servers of the host or any hardware are not used and the machines do not rely on any systems rather than Hypervisor itself. This makes the host system run multiple Virtual machines and run a huge amount of data in the same system.
- All the virtual machines are separated from each other and none is aware of other virtual machines. But, if any virus or malware attack happens and if anyone VM fails, the other one works well and carries out the tasks assigned to the system. Hypervisor protects the VMs from any type of attacks, be it external or internal.
- Hypervisors can be automated for resource allocation and we can allocate whatever resources we need to the operating systems. We can allocate the resources based on the user’s priority of applications. The resource allocation either can be automated or manual. Users can customize the applications if needed. If we use a hardware type of hypervisor, it will help to free the servers, and hence cost is saved. This helps to free the space of servers as well. An admin is needed to manage the physical server and to maintain the server always. If the server is not working, it will affect the entire system working on the same hypervisor.
- Hypervisors of type 2 are called hosted hypervisors which runs as an application inside the host system. This cannot access the host hardware directly but can run any number of operating systems within the host system which is not limited. This system makes use of the host system to use the CPU and storage if needed. This will make the system slow if there are multiple operating systems. An admin is not needed and if we have an operating system, we can install and use the hypervisor.
- Another type of hypervisor is a kernel-based virtual machine which has the features of both physical and software type hardware. The operating system is Linux and all the features of this hypervisor can be added or managed with Linux systems. Storage, memory management is good in KVM and this is not slow when compared to other hypervisors. The virtual machines are isolated and this helps to secure the virtual machines and protect from any cyber-attacks if occur.
Advantages and Disadvantages
Advantages and disadvantages of hypervisor in cloud computing are:
- Hypervisor makes it easy to manage multiple operating systems in a single host system. Without hypervisor, it would make conflicts on the operating system’s hardware and the system might end up without working. Hence, managing the systems is an advantage of the hypervisor.
- The independence and co-existence of different operating systems are made possible by hypervisor. All the operating systems are made to work independently as different systems will have different sorts of work. If the work needs to be cooperated, hypervisor does that and sends it to the host system.
- Security offered to the systems by hypervisor should be appreciated as both external and internal virus attacks are avoided by VMM. This makes hypervisor a protector for the underlying systems.
- Free hypervisors are available in the market but most of the time, those hypervisors will not be going well with the enterprise needs. While searching for a hypervisor, it is difficult to find one within the budget and the one that is reliable. This is one disadvantage of the hypervisor. Also, with the central server and main component, the hypervisor is always prone to cyber-attacks and it is necessary to protect the hypervisor and operating systems from those attacks. Domestic computers do not support hypervisors and for them, virtualization without hypervisors is the option available.
The use of hypervisor is helpful to manage virtualization in the systems and to manage the work easily in different operating systems. All the management and support depend on the hypervisor and it is important while selecting the same. Though the initial setup is costly, it is profitable in the long run.
This is a guide to Hypervisor in Cloud Computing. Here we also discuss the introduction and working of a hypervisor in cloud computing along with advantages and disadvantages. You may also have a look at the following articles to learn more –