I'm going to assume this is from the perspective of KVM. If its for Xen, some of the below may or may not apply. Generally, LUN's are per VM, so any export limits on your storage and LUN count ...

I'm doing a POC of Incus at work. Cheap Hetzner iron is good for us, and we're looking to expand virtualization capabilities. The POC is great, but Incus defaults to using a directory for storage, ...