Main menu


Virtualization: VM and Hypervisor

Virtualization: VM and Hypervisor

today my topic is virtualization I will explain virtualization and some related concepts such as a physical machine a virtual machine and a two types of hypervisor at the end of the article I would also talk about the advantages and disadvantages of virtualization.

a physical machine is a computer like Windows it has CPU, memory, hard disk and a network connection in the context of virtualization the physical computer is called a host. virtualization is the process of a using special software on a physical machine to create virtual machines this is special software is called hypervisor, a virtual machine is called a guest there are three important points about virtual machines

1. we can create and around as many virtual machines as we like as long as their host CPU, RAM and other resources allow. Ram is almost always the main limiting factor together all the virtual machines share the same resources of the host yet each virtual machine works independently

2. a virtual machine is little more than a fowl sitting on a hard drive but a to users a virtual machine appears an X no differently from a physical computer.

3. a virtual machine can be configured to use not only a different operating system but also a different type of a CPU storage drive or Nick that is a host.

now let's talk about the special software that it creates and aroused virtual machines hypervisor there are two types of hypervisor type one and type two type one hypervisors run directly on top of the hosts hardware that's why they are called bare-metal hypervisors they can cure the hardware and manage virtual machines. type 1 hypervisors act just like operating systems some examples type 1 hypervisors Xen, vmware, EXI, microsoft hyper-v or KVM.

a type 2 hosted hypervisor most frequently referred to as virtual machine monitor (VMM) is like application program running on top of the call a tional operating system such as Windows, Linux or Mac OS virtual machines are created and managed by both virtual machine monitor through the host operating system examples of a type 1 hypervisor include VMwareWorkstation, Vmware Player, virtual box or parallels Desktop for Mac.

now let's talk about four advantages of virtualization

1. saving money

without virtualization we might buy several different physical servers in our data center or many workstations for testing or learning purpose in our classroom or lab, with virtualization we can place multiple virtual machines servers or workstations on a single powerful physical system, with virtualization we also reduce device storage space and electrical power use substantially.

2. simplified management

is another advantage because we do not have to manage so many separate devices.

3. threat isolation

in a virtual environment the isolation of each gasta system means a problem with one guest does not affect the others security attacks on a guest may have a little effect on a host of physical machine. this feature is a great for a cyber security lab.

4. system backup and recovery

virtual machines are simply false and like any file they can be copied and they can be restored the feature of a snapshot enables to create a multiple identical copies of a one virtual machine if something happens to the system what we need is a simply to restore the copy.

but there's always a two sides to everything there are some disadvantages of virtualization here are four

1. compromised performance

because the host and all guests share limited resources

2. increased complexity

managing virtual machine is more complex than managing physical machines learning curve can be steep and more new skills are required as virtualization becomes more popular.

3. there's a big risk since we keep all our eggs in one basket if a host machine fails all is virtual machine we all fails to this type of risk is called single point of failure.

4. license cost

this problem is becoming less of a problem but it is still an important considering factor.