when you are creating a Virtual Machine Scale Set, you have the opportunity to optionally specify availability zones:
I understand when you specify a single or multiple AZs, the VMs will be created only in those very zones and Azure will try to evenly balance them across them.
What I don't understand is how the VMSS behaves when checking none of the availability zones? Does that mean Azure has complete freedom of choosing which datacenter the VM is created in? Are then multiple VMs restricted only to the datacenter of Azure's choosing or can the placement be fully arbitrary?
Thanks in advance!