For the life of me, I can't work out what the differences are between Update-AzureRmVmss, Update-AzureRmVmssInstance and Update-AzureRmVmssVM in relation to Azure Resource Manager (AzureRM), even after reading the documentation.
I'm looking to run a command that will update all my VMs in my Azure VMSS (virtual machine scale set) regardless of the number of instances. The upgrade policy is set to manual.