I have written numerous articles on how to connect your server or workstation to an iSCSI server but not many on what the various software options are, how they differ, or where to find them. That's exactly what I'll cover in this article. I will start with why you need an iSCSI Server and then move on the cover the various free and commercial software options to turn a Windows Server into a shared file store. Options include - OpenFiler, FreeNAS, StarWind and HP VSA.
Why you need a software-based iSCSI Server
If you have more than one PC, you need a centralized place to access files. Sure, you can buy a hardware-based iSCSI SAN like the Iomega Storcenter ix2-200 or the Drobo Pro (a couple of my favorites). However, why spend extra dollars on hardware if you already have a Windows server laying around?
If you cannot already picture why you need an iSCSI Server, here are a few reasons:
- Centralized storage and file share
- iSCSI uses more efficient block level transfer than SMB file sharing, thus you will get better performance by having your PCs gain shared file access using iSCSI
- Much more cost effective option than a Fibre Channel (FC) SAN
- Required as centralized storage when using VMware vSphere / ESX Server to perform advanced features
What are the options available in order to create a software-based Windows iSCSI Server?
There are many options available to make a Windows server into a software-based iSCSI server. Likely, there are so many out there that I will miss one or two when providing the list below...
- OpenFiler - for a number of years I have been using and writing about OpenFiler. At a previous company, we even used OpenFiler as centralized storage for our Test & Development VMware ESX Servers. I have connected ESX Server, Hyper-V, Windows Server, and Windows 7 all to OpenFiler (see my articles in the next section).
OpenFiler is a free and open-source solution that works very well. It is a Linux-based appliance that can be installed either with installation media (created from the downloadable ISO) or you can either download a VMware virtual appliance.
In fact, I enjoyed using OpenFiler so much I created the following article on how to Use OpenFiler as your Free VMware ESX SAN Server.
Figure 1: OpenFiler
- FreeNAS - like Open Filer, FreeNAS is an opensource iSCSI SAN. Honestly, I have never used it and the website is not as pretty as the rest but the folks over at Train Signal have used it and they wrote a series of articles on it (below). I read these articles and was impressed with what FreeNAS can do so perhaps you should check it out as well:
- Build Your Own Open Source NAS Device Using FreeNAS – Part 1
- Build Your Own Open Source NAS Device Using FreeNAS – Part 2
- How to Setup iSCSI Drive Using FreeNAS
Figure 2: FreeNAS
- StarWind Software - recently I saw a webcast covering Starwind's iSCSI solution which was presented by fellow vExpert Greg Shields. Starwind's solution is impressive! Not only do they have a free iSCSI server option but, from there, you can upgrade to a one of 4 advanced versions (see Starwind's Editions page). In fact, one of their commercial options provides you with active-active high availability and data synchronization over a WAN / Continuous Data Protection (CDP). They have a number of videos that cover how to install and use their iSCSI solution to help you get it installed and running.
Figure 3: Starwind iSCSI Enterprise
- HP / Lefthand P4000 /VSA - HP bought Lefthand who created both SAN hardware and SAN virtual software appliances. Thus, the Lefthand VSA was renamed the HP P4000 VSA. The VSA is unique in that it does not run inside a Windows server at all. Instead, the VSA runs inside a VMware ESX server. The other unique thing about it is that it uses the local disk space on each ESX server that it runs on to create a virtual distributed SAN, across the ESX servers. By doing this, this unused disk space is used and you don't need a separate physical server for your iSCSI SAN (as long as you were already using VMware ESX). There is no free version of VSA but there is a free 30 day trial. Unlike the other solutions, Lefthand's VSA is the only solution that VMware supports if you want to use their Site Recovery Manager (SRM) solution.
I wrote this article covering Lefthand's VSA - Installing LeftHand's virtual storage appliance in VMware ESX - and Mike Laverick over at RTMF-Ed.co.uk offers the following whitepaper on Installation and Configuration of Lefthand Networks VSA.
Connecting your servers and PC clients to the iSCSI SAN
At the start of this article, I mentioned how I had written a number of articles on how to connect your PC or server to an iSCSI SAN. Once you get your choice of iSCSI SAN up and running, here are links to those articles:
- Connect VMware ESX Server to a Free iSCSI SAN
- How to connect Windows Server 2008 and Windows Vista to an iSCSI Server
- Connecting Windows 7 to an iSCSI SAN
In summary, using iSCSI SAN software to create an iSCSI SAN is a great option. It allows you to use hardware that you already have or, at the minimum, use industry standard, lower cost servers instead of expensive proprietary SAN equipment. I encourage you to try these free or trial software-based SAN solutions today!
If there are other software-based SAN solutions that you use which I haven't mentioned, please contact me as I would like to hear about them!