More and more small and medium (SMB) offices and home offices (SOHO) (less than 50-75 users) are moving toward virtualization. Microsoft Hyper-V is a very attractive choice from the cost perspective. Those offices do not need a lot of storage capacity. They might be running just a few virtual servers for directory services, file- and print, email and databases. 1,2, or 3 TB is often what they use at the most.
For redudancy a minimum of two virtualization hosts are used. iSCSI is the cheapest way to have shared storage supported by Microsoft Hyper-V. While ESX(i) is not critical on the iSCSI support (basically each iSCSI implementation will work, Hyper-V is much more critical. To be able to create a Windows Server 2008 failover cluster, the shared iSCSI storage needs to support iSCSI SPC-3 Persistent Reservation. The more expensive shared storage solutions (around $10.000 ) from known vendors like Dell, HP do support iSCSI Persistent Reservations but the small, often home use storage arrays mostly do not.
There are two solutions for ‘cheap’ (free to $8000) iSCSI storage which can be used for Windows Hyper-V clustering:
A software target is installed on regular server or desktop hardware running either Windows operating system or Linux. For Windows operating systems three free, unlimited solutions are available:
1. Microsoft Windows iSCSI target. This is a free addon. It can only be installed on Windows Server 2008 R2 and has some basic functionality.
2. StarWind free iSCSI SAN. StarWind released the free software in May 2011. It can be installed on Windows desktop os like XP, Vista or Windows 7 and on Windows Server os. The free edition has some good functionality. Read about it here. It does not have a limit on the storage capacity and can be used in production environments.
3 Microsoft Storage Server. Microsoft Storage Server is available for download for MSDN and Technet Plus subscribers. See here how.
–FreeNAS and Openfiler running on Linux server. A bit more complex to install and use if not familiar with Linux.
-Youngzsoft iSCSI Cake
-Open-E iSCSI R3 (in July 2009)
-SANsymphony 6.x or SANmelody 2.0.3 (with adjusting the registry)
–Kernsafe iStorage Server
The hardware storage solutions that will work with Windows Server 2008 are listed here
Synology has a couple of good storage devices
Some of the QNAP devices support Persistent Reservations. They are the cheapest hardware solutions available. Models QNAP TS-439U , QNAP TS-259 and QNAP-859 support iSCSI persistent reservations.
Drobo does not seem to support Windows 2008 clustering
The Iomega IX12-300r supports Hyper-V as well as VMware. Stuffed with 4 TB data the listprice is $ 5000,-
The entry level iSCSI storage of Dell supports Hyper-V: PowerVault MD3220i $ 5400, without drives!
Sansdigital MobileRAID MR8S supports SCSI-3 persistent reservations and costs $ 3050,- (diskless cabinet)
FalconStor Network Storage Server (NSS) also supports Windows Server 2008 clustering
For an overview of low cost storage devices for vSphere have a look at this thread.
An overview of the arrays which start at around $ 10,000. can be found in this article. Some of the arrays mentioned are HP P2000 G3 MSA, NetApp FAS2040, EMC VNXe