Hypervisors

A hypervisor or virtual machine monitor (VMM) is computer software, firmware, or hardware, that creates and runs virtual machines.

A computer on which a hypervisor runs one or more virtual machines is called a host machine, and each virtual machine is called a guest machine. The hypervisor presents the guest operating systems with a virtual operating platform and manages the execution of the guest operating systems.

There are 2 types of hypervisor

  Type 1 hypervisors

• Loaded directly on the physical hardware
• Hyper-v  ( Microsoft )
• ESXi     ( VmVare)
• KVM     ( Linux based hypervisor 
• Comomly used in the datcenter becuase they have direct access to the physical server hardware and we get the best performance

   Steps involved building Type 1 hypervisor

1. Load the hypervisor on the physical server
2. Run virtual machines on top
3. Run windows server 2012 
4. Enable applications like Microsoft exchange or IIS web services

Type 2 hypervisors

• Loaded in OS running in the hardware
• Workstation (VmVare)
• Oracle VM (Virtual Box )
• Parallels (Mac )
• Fusion (VmVare )
• Commonly used by IT professionals
• You can use this on existing computers
• Some use case would be running windows on Mac or running linux on windows
• As we have extra layer of software performance is not good as compared to Type 1 hypervisors