AZ-900 Certification Notes

Chapter 4 - Virtual Machines

What is a Virtual Machine?

A virtual machine is the virtualization or emulation of a computer system. They are based on computer architectures and provide the same functionality as a physical machine.

Features

• Infrastructure-as-a-Service (IaaS)
  • Manage everything except the hardware. This includes the network components
• Tools
  • Use the Azure Portal to manage large numbers of VMs and even hybrid clouds
• Compliance
  • Use Azure blueprints to make your VMs comply with company guidelines
• Recommendations
  • Azure will recommend improvements to ensure better security, higher availability, and greater performance
• Choice
  • Choose amount of RAM, number of CPUs, Windows or Linux

Pricing

• Calculated Hourly
  • The more CPUs, GPUs, and amount of RAM you want, the more you pay per hour

Use Cases

• Pros:
  • Control
    • Use virtual machines when you need to control all aspects of an environment or machine
  • Application
    • Install specific applications on your Windows or Linux machines
  • Existing Infrastructure
    • You can move existing resources and virtual machines to Azure from on-premises or another cloud provider
• Cons:
  • Not for Everything
    • If you can use another Azure service instead, it is often worth it
  • Maintenance
    • A lot of maintenance with VMs. Operating system updates, patches, security concerns

Exam Tips

Virtual Machines are at the core of Azure compute and are widely used.

• A virtual machine is your machine exclusively
• You don't buy, own or control any hardware. Azure does this
• Virtual machines are an IaaS offering where you are responsible for the entire machine
• Azure virtual machines take advantage of Azure tools
• Pricing goes up as resources go up, and you pay by the hour