Azure Classroomnotes 07/Sep/2022

What is Virtual Machine (VM)

• VMs can be created on the physical server by using a software called as hypervisor
• Hypervisors are of two types.
  • Hypervisor on existing OS => hyper V, Virtual Box, Vmware Workstation, KVM
    
  • Hypervisor as OS on Physical Server => Vmware ESXI
    
• Datacenter: Typical Datacenter has racks with blade servers and generally on each blade server we install hypervisor os like vmware esxi, Depending on the needs of the enterprise we create virtual machines which teams will be using to deploy/use for applications
  
• Any Cloud charges for the VM in the
  • unit of hours
  • Server Operating Systems (Linux => free, Windows Server => hourly charges)
  • For instance size (CPU and RAM)
  • For virtual disk
• For purchasing Compute we generally have 3 major models
  • On-demand (No-commitments) => Costlier Option
  • Reservations (1 year or 3 year commitments) => discounts are upto 63% (Azure)
  • Spot/Bidding Instance => Cheapest but not reliable