Microsoft have made the Iscsi Software Target available for public download. So if you have a Windows Server 2008 R2 you can use it as a NAS device. Not recommended for big solutions, but perfect for test/demo and small companies/ branch offices.
It's real perfect for testing out clustering featues, like Hyper-v, Exchange and so on.
The Microsoft iSCSI Software Target 3.3 provides storage (disks) over a TCP/IP network. It turns a computer running Windows Server into a storage device which provides shared block storage. You can use Microsoft iSCSI Software Target 3.3 to perform a variety of storage-related tasks, including the following:
- Provide shared storage for Hyper-V to enable high availability and live migration
- Consolidate storage for multiple application servers (i.e. Microsoft SQL Server or Hyper-V)
- Provide shared storage for applications hosted on a Windows failover cluster
Enable diskless computers to boot remotely from a single operating system image using iSCSI
More info here
And download are here
If download link are missing just go to Microsoft download center and search for Microsoft ISCSI Software Target (and you will also find the never version when it arrives ;-)