Hyper-V SCSI vs IDE Boot

Looking at the number of searches relating to this issue, it appears to be the biggest concern about Hyper-V so far.

While it is not acceptable that a Virtual Machine must boot from an IDE drive interface when the underlying storage is SCSI, it is possible that the IDE performance in Hyper-V could be better than pre-existing virtual SCSI storages (Virtual Server, for example). The virtualization team on Microsoft explains it better, but the new synthetic drivers on Hyper-V utilizes a much better way of providing virtualization, resulting in better performance. It is possible that the IDE driver in Hyper-V can perform better than SCSI driver in Virtual Server 2005.

We have yet to run a performance comparison between Hyper-V IDE and Virtual Server 2005 SCSI. However, once the integration services (synthetic drivers) installed on a Windows 2003 guest machine, it appears pretty fast.

Also, a SCSI hard drive can be added to a Virtual Machine and used as the data storage. We often seperate boot and data drives on servers anyways. Having a seperate data drive makes it easy to backup virtual machine data.

These of course, are just work arounds until Microsoft figures a way to boot Hyper-V machines from SCSI.

They must be working hard on it. 

Hopefully soon we will be able to run some performance comparison between Hyper-V and Virtual Server guest machines.