See [[Creating an Azure VM]]. VMs provide infrastructure as a service (IaaS). User still needs to configure, update, and maintain, the software that runs on the VM. Scaling VMs in Azure: Azure can run single instances or a group VMs to provide high-availability, scalability, and redundancy. Azure can manage the grouping of VMs through features such as **scale sets** and **availability sets**. **Scale Sets:** Allow to centrally manage, configure, and update a large number of VMs within minutes. Automatically deploys a load balancer to ensure that resources are being used efficiently. VM instances can be increased or decreased based on demand or a defined schedule. **Availability Sets:** Designed to ensure that VMs stagger updates along with having varied power and network connectivity in order to prevent losing all VMs in the event of a network or power failure. This is accomplished by grouping VMs in two ways, **update domain** and **fault domain**. **Update Domain:** Groups VMs that can be rebooted at the same time. This allows for updates to be applied while knowing that only one update domain group is offline at a time. The current update group is provided 30-minutes for recovery processes/efforts before the next update domain begins. **Fault Domain:** Groups VMs by common power source and network switch. Essentially, fault domains are are domains connected to different power and networking resources. Example: Fault domains 1, 2, and 3 are all separated by being placed on different power and networking resources. If one goes down the other two are not affected. There is no additional cost for configuring availability sets, you only pay for the VM instances created. > [!NOTE] > By default, an availability set splits your VMs across up to three fault domains. ### Azure Service Health - **Azure Status** is a broad picture of the status of Azure globally. Azure status informs you of service outages in Azure on the Azure Status page. The page is a global view of the health of all Azure services across all Azure regions. It’s a good reference for incidents with widespread impact. - **Service Health** provides a narrower view of Azure services and regions. It focuses on the Azure services and regions you're using. This is the best place to look for service impacting communications about outages, planned maintenance activities, and other health advisories because the authenticated Service Health experience knows which services and resources you currently use. You can even set up Service Health alerts to notify you when service issues, planned maintenance, or other changes may affect the Azure services and regions you use. - **Resource Health** is a tailored view of your actual Azure resources. It provides information about the health of your individual cloud resources, such as a specific virtual machine instance. Using Azure Monitor, you can also configure alerts to notify you of availability changes to your cloud resources.