What is Virtualization?

Virtualization (or virtualization), in computing, is the creation of a virtual (rather than actual) version of something, such as a hardware platform, operating system, storage device, or network resources.

what are the types of hardware virtualization?

Full virtualization: Almost complete simulation of the actual hardware to allow software, which typically consists of a guest operating system, to run unmodified Partial virtualization: Some but not all of the target environment is simulated. Some guest programs, therefore, may need modifications to run in this virtual environment.

Paravirtualization: A hardware environment is not simulated; however, the guest programs are executed in their own isolated domains, as if they are running on a separate system. Guest programs need to be specifically modified to run in this environment.

What are the benefits of virtualization?

Virtualization is the creation of virtual machines and managing them from one place. It allows the resources to be shared with a large number of network resources. Virtualization is having lots of benefits and they are as follows:
1. It helps in saving lots of costs and allows to easily maintaining it, in less cost.
2. It allows multiple operating systems on one virtualization platform.
3. It removes the dependency on heavy hardware to run the application.
4. It provides consolidating servers that are used for the crashing of a server purpose
5. It reduces the amount of space being taken by data centers and company data.

What is the purpose of a Hypervisor?

The hypervisor is a program that manages the virtual machine. It also acts like a virtual machine manager that manages the many virtual machines from one place. It allows multiple operating systems to share a single hardware host. Each operating system in this consists of its own defined space consisting of space, memory and processor. It is used as a controller program to control host processors and resources. It separates out the layer between many operating systems so that one can’t conflict with another one.

How ESX server related to VMWare?

ESX server is the enterprise edition of VMWare. It provides server virtualization platform that allows many operating systems to be shared together in a convenient way and consists of a centralized management platform that is also known as virtual centre. ESX server is a virtualization technique that is used to create cloud applications and allows easy development of cloud platforms. It is related to VMWare as it is the upper layer of it.

What is the difference between ESX and GSX server?

GSX server acts as type 2 hypervisor that gets installed on the host operating system’s hardware like windows and Linux. VMWare workstation gets mixed up with GSX server to provide it more functionality to run your applications and operating systems. ESX server on the other hand, is type 1 hypervisor that runs its software directly on the system’s hardware and it doesn’t require any operating system prior to its installation. It is a level 0 hypervisor and it has its own operating system.

How VMWare Kernel different from other kernels?

VMWare kernel is a proprietary kernel that means that it is a registered kernel by VMWare Company and it is not based on any other kernel architecture or any other operating system. VMWare consists of a kernel that requires an operating system to boot it. A service console is being provided when the VMWare kernel is booted.

What are the features provided by VMWare for easy access?

VMWare provides several features to make it easy for the user to access and maintain it. The features are as follows:

  • VMWare provides web browser interface
  • It provides easy to use wizard to configure the settings
  • It provides tools to easily create hosts and maintain it from one place
  • It provides easy maintenance of Virtual machines
  • It provides easy graphics to configure the VMWare settings for securit

What are the different components used in VMWare infrastructure?

The different and major components used in VMWare infrastructure is as follows:

  • VMWare infrastructure consists of the lowest layer which acts as a ESX server host.
  • VMWare infrastructure also use the virtual centre server that keep tracks of all the VM related images and manage it from one point.
  • VMWare infrastructure (VI) client: this allows the client to interact with user’s applications that are running on VMWare.
  • Web browser is used to access the virtual machines.
  • License server is used to create a server that provides licensing to the applications
  • Database servers are used to maintain a database.

What is QEMU?

QEMU is a generic and open source machine emulator and virtualizer. When used as a machine emulator, QEMU can run OS and programs made for one machine (e.g. an ARM board) on a different machine (e.g. your own PC). By using dynamic translation, Qemu achieves very good performance.

What is KVM (Kernel Virtual Machine)?

KVM is a Linux kernel module that allows a user space program to utilize the hardware virtualization features of various processors.

Difference Between Qemu and KVM

QEMU

  • Qemu is a complete and standalone software, it emulates the target operating system.
  • Qemu supports Para virtualization
  • To emulate more than just the processor, Qemu includes a long list of peripheral emulators: disk, network, VGA, PCI, USB, serial/parallel ports, etc.

KVM

  • KVM supports full virtualiztion.
  • KVM is a fork of the Qemu executable ,Both teams work actively to keep difference at a minimum.
  • Apart from the processor state switching, the kernel module also handles a few low-level parts of the emulation, like the MMU registers (used to handle VM) and some parts of the PCI emulated hardware.

Define snaphot of a virtual Machine?

A snapshot is the state of a virtual machine and generally, its storage devices, at an exact point in time. Snapshots are taken by simply giving an order to do so at a given time, and can be “reverted” to on demand, with the effect that the VM appears exactly as it did when the snapshot was taken. Snaphot is useful as an extremely rapid backup technique, prior to a risky operation.

What is memory virtualization?

Memory virtualization, aggregating random-access memory (RAM) resources from networked systems into a single memory pool.

What is Stoarge Virtualization?

Storage virtualization, the process of completely abstracting logical storage from physical storage.Virtual disk drive, a computer program that emulates a disk drive such as a hard disk drive or optical disk drive in virtualized setup.

What is virtual Machine Cloning?

Virtual Machine Cloning is a method of creating a copy of an existing virtual machine with the same configuration and installed software as the original.The existing virtual machine is called the parent of the clone. When the cloning operation is complete, the clone is a separate virtual machine.

What are the types of cloning in virtualization?

A full clone is an independent copy of a virtual machine that shares nothing with the parent virtual machine after the cloning operation. Ongoing operation of a full clone is entirely separate from the parent virtual machine.

A linked clone is a copy of a virtual machine that shares virtual disks with the parent virtual machine in an ongoing manner. This conserves disk space, and allows multiple virtual machines to use the same software installation.