What scale sets are for?
Customers may add standard VMs to scales sets.
Azure Virtual Machine Scale Sets (VMSS) allow creating and managing a group of load-balanced VMs. Azure consumers who deliver services requiring high availability and large scale leverage scale sets to ensure application resiliency.
With Flexible orchestration mode, customers can add standard Azure VMs to Azure VM Scale Sets. Microsoft Azure reports those machines as both Azure VM and Azure VMSS instance. In Cloudaware CMDB, those machines are may be displayed as duplicates in related objects of a selected Azure VM Scale Set:
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