2.2.2 Describe Azure VMs

Description of Azure VMs.

VMs provide IaaS in the form of a virtualized server and can be used in many ways. All software on the VM can be configured, these are ideal when you need:

• Total control over the OS

• Ability to run custom software

• Use custom hosting configurations

You need to configure , update and maintain any software on the VM. An already created image can be used to rapidly provision VMs. An image is a template and may already include an OS and other software.

Scale VMs in Azure

VM scale sets let you manage a group of identical load-balanced VMs. Using VM scale sets lets Azure automate the work required to setup multiple VMs with the same purpose. Scale sets allow central management and can be automatically increased or decreased in response to demand. VM scale sets automatically deploy a load-balancer to make sure resources are used efficiently.

VM Availability Sets

Designed to ensure VMs stagger updates and have varied power/network connectivity, which prevents you losing all your VMs with a single network or power failure. This is achieved using an update domain and a fault domain.

• Update Domain: Groups VMs which can be rebooted simultaneously. This allows updates to be applied to all machines in the group. Each update group is given 30-mins recovery time before the next update group begins.

• Fault Domain: Groups VMs by common power source & network switch. Default splits your VMs into up to three fault domains. This protects against physical power or network failures.

Examples of VM Use

• Testing and development. VMs are a quick and easy way to make different OS and app configurations. VMs can be deleted when not needed.

• Running cloud applications. An app may need to handle fluctuations in demand, shutting down or quickly starting VMs to meet demand requirements means you only pay for resources you use.

• Extending data center to the cloud. You can extend capabilities of an on-prem network by creating a virtual network in Azure and adding VMs to that. Apps like SharePoint can run on an Azure VM.

• Disaster Recovery. If a primary data center fails, VMs can be created on Azure to run critical apps, they can then be shut down when the data center is operational gain.

Move to the Cloud with VMs

A VM can create an image of a physical server and host it with little to no changes for a lift-and-shift operation.

VM Resource

• Size (purpose, number of processor cores, amount of RAM)

• Storage Disks (hard disk drives, solid state drives, etc.)

• Networking (virtual network, public IP address and port configuration)