AZ-104 Practice Question 6: VMSS Orchestration Mode
Microsoft Azure Administrator Associate (AZ-104) · Test 1 · question 6 of 10
An application team runs a Virtual Machine Scale Set created in Uniform orchestration mode. New requirements have arrived: the instances must be protected by Azure Backup, and two long-lived virtual machines that already exist must be brought under the same scale set for load balancing.
What must you do to satisfy both requirements?
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Answer:
Uniform orchestration manages scale-set-specific VM objects (Microsoft.Compute/virtualMachineScaleSets/virtualMachines). Those instances are not standard IaaS VMs, so they are not compatible with Azure Resource Manager tagging, Azure Backup, or Azure Site Recovery, and existing VMs cannot be added to a Uniform scale set. Flexible orchestration manages standard Microsoft.Compute/virtualMachines resources, supports Azure Backup, and explicitly supports adding and removing existing VMs. Because the orchestration mode is fixed at creation time and cannot be changed afterwards, meeting both requirements means standing up a new Flexible scale set and moving the workload, which is also the mode Microsoft now recommends by default.
Option A does not help. Automatic OS image upgrades are a Uniform-only feature and have nothing to do with backup; Azure Backup still cannot protect Uniform instances.
Option C describes an operation Azure does not offer. The orchestration mode is defined when the scale set is created and cannot be changed or updated later.
Option D mixes two mutually exclusive availability constructs. A VM belongs either to an availability set or to a scale set, and putting a VM in an availability set does not make it a member of the scale set.
Reference: Orchestration modes for Virtual Machine Scale Sets in Azure