Scale Sets – Azure’s VM auto-scaling service.
Azure Virtual Machine Scale Sets enable you to create and manage a group of identical, load-balanced VMs. They feature automatic OS updates, support for both Windows and Linux VMs, and integration with Azure Load Balancer. Scale Sets include automatic instance repairs, flexible orchestration modes, and support for spot instances. The service provides automatic scaling based on metrics or schedules, enables rolling upgrades for zero-downtime updates, and supports custom script extensions for configuration.