Virtual machine scale sets (VMSS) are an Azure compute resource that you can use to deploy and manage a set of identical VMs. With all VMs configured in the same way, scale sets are designed to support true auto scale, and no pre-provisioning of VMs is required. It helps in provisioning multiple identical virtual machines connected to each other through a virtual network and subnet.
VMSS creates a set that can be created, configured, and managed as a unit. All virtual machines are part of this unit and any changes made are applied to the unit, which in turn applies it to virtual machines using a pre-determined algorithm.
It allows these virtual machines to be load balanced using Azure load balancer or application gateways. All the virtual machines could be either Windows or Linux operating system. They can run automated scripts using a PowerShell extension...