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FreeNAS or OpenFiler.

I think FreeNAS (the BSD based one) is lighter and easier, as OpenFiler seems to be going in a more "fully featured" direction with less support for older hardware, but they're both good.

What you want is cheap 5U rack servers with either OpenFiler or FreeNAS. Personally, I like openfiler better. iSCSI is going to be the way to go unless you want a thick OS on the server and all the other admin issues that come with that. Plus, with openfiler you can still do block level snapshotting and change replication. Also, I've heard good things about Open-e as well. And if you want to mess with ZFS, there's OpenSolaris.

What you do is get yourself a huge (4 or 5U) barebones server from newegg or a cheaper place. Make sure to get a couple of good SATA RAID controllers. Not FakeRAID! SAS would be better, but the drives are a lot more, even for the nearline drives that are basically SATA drives with a SAS interface. Adaptec makes some real SATA raid cards, and there's 3Ware as well. You don't have to worry a lot about the cache, but if it isn't battery backed, you're going to write though it anyway. Who cares, you have 16 spindles! Load it with a bunch of drives. They don't have to be the biggest, anyway more spindles means more performance. 16 500GB drives is going to be fine, for instance, because then you can take 1/3 of that for RAID 6, have some hot spares, etc. Get the slowest drives you can, maybe get a little SSD to use as a boot drive (there are small ones for around $100). You could even boot from a USB key if you feel like the hassle. You don't need a ton of processor. A celeron would probably work, but you probably do want something 64 bit so you can put a bunch of RAM in it as you get more advanced.

Also check out Storage Search. Not a very well designed site but tons of goof info under iSCSI and SAN and NAS.. If you're rich, you might try out an EqualLogic, they are around $28,000 for 8TB but pretty slick.

The SAN argument is that your storage is so precious it must not be stranded. If you're paying $50K/TB with drives, controllers, FC switches, service, software, support, installation and all that jazz then that's absolutely true. If you're doing something like OpenFiler clusters on BackBlaze 90TB 5U Storage Pods for $90/TB and 720 TB/rack you have a different point of view. As for somebody showing up to replace a drive, I think I could ask Jimmy to put his jacket on and shuffle down to the server room to swap out a few failed drives every couple months - that's what hot and cold spares are for and he's just geeking on MyFace anyway. Low utilization? Use as much or as little as you like - at $90/TB we can afford to buy more. We can afford to overbuy our storage. We can afford to mirror our storage and back it up too. In practice the storage costs less than the meeting where we talk about where to put it or the guy that fills it. If you want to pay for the first tier OEM, it's available but costs 10x as much because first tier OEMs also sell SANs.

Openfiler does CIFS/NFS and offers iSCSI shared storage for Oracle, Exchange and SAP. If you need support, they offer it. OpenFiler is nowhere near the only option for this. If you want to pay license fees you could also just run Windows Server clustered. There are BSD options and others as well. Solaris and Open Solaris are well spoken of, and ZFS is popular, though there are some tradeoffs there. Nexenta is gaining ground. There's also Lustre, which HP uses in its large capacity filers. Since you're building your own solution you can use as much RAM for cache as you like - modern dual socket servers go up to 192GB per node but 48GB is the sweet spot.

Now that we've moved redundancy into the software and performance into the local storage architecture, moving storage to the edge is exactly what we want to do: put it where you need it and if you need a copy for data mining then mirror it to the mining storage cluster. We still need some good dedicated fiber links to do multisite synchronous replication for HA, but that's true of SAN solutions also. We're about 20 years past when we should have ubiquitous metro fiber connections, and that's annoying. Right now without the metro fiber the best solution is to use application redundancy: putting a database cluster member server in the DR site with local shared storage.

Oh, and if you need a lot of IOPS then you choose the right motherboard and splurge on the 6TB of PCIe attached solid state storage per BackBlaze pod for over a million IOPs over 10Gig E. If you need high IOPS and big storage you can use adaptor brackets and 2.5" SSDs or mix in an array of The Collossus, though you're reaching for a $6K/TB price point there and cutting density in half but then the SSD performance SAN has an equal multiple and some serious capacity problems. If you go with the SSD drives you would want to cut down the SAS expanders to five drives per 4x SAS link because those bad boys can almost saturate a 3Gbps link while normal consumer SATA drives you can multiply 3:1.

If you're more compute focused then a BackBlaze node with fewer drives and a dual-quad motherboard with 4 GPGPUs is a better answer. At the high end you're paying almost as much for the network switches as you are for the media. If you're into the multipath SAS thing then buy 2x the controllers and buy the right backplanes for that - but

The SAN argument is that your storage is so precious it must not be stranded. If you're paying $50K/TB with drives, controllers, FC switches, service, software, support, installation and all that jazz then that's absolutely true. If you're doing something like OpenFiler clusters on BackBlaze 90TB 5U Storage Pods for $90/TB and 720 TB/rack you have a different point of view. As for somebody showing up to replace a drive, I think I could ask Jimmy to put his jacket on and shuffle down to the server room to swap out a few failed drives every couple months - that's what hot and cold spares are for and he's just geeking on MyFace anyway. Low utilization? Use as much or as little as you like - at $90/TB we can afford to buy more. We can afford to overbuy our storage. We can afford to mirror our storage and back it up too. In practice the storage costs less than the meeting where we talk about where to put it or the guy that fills it. If you want to pay for the first tier OEM, it's available but costs 10x as much because first tier OEMs also sell SANs.

Openfiler does CIFS/NFS and offers iSCSI shared storage for Oracle, Exchange and SAP. If you need support, they offer it. OpenFiler is nowhere near the only option for this. If you want to pay license fees you could also just run Windows Server clustered. There are BSD options and others as well. Solaris and Open Solaris are well spoken of, and ZFS is popular, though there are some tradeoffs there. Nexenta is gaining ground. There's also Lustre, which HP uses in its large capacity filers. Since you're building your own solution you can use as much RAM for cache as you like - modern dual socket servers go up to 192GB per node but 48GB is the sweet spot.

Now that we've moved redundancy into the software and performance into the local storage architecture, moving storage to the edge is exactly what we want to do: put it where you need it and if you need a copy for data mining then mirror it to the mining storage cluster. We still need some good dedicated fiber links to do multisite synchronous replication for HA, but that's true of SAN solutions also. We're about 20 years past when we should have ubiquitous metro fiber connections, and that's annoying. Right now without the metro fiber the best solution is to use application redundancy: putting a database cluster member server in the DR site with local shared storage.

Oh, and if you need a lot of IOPS then you choose the right motherboard and splurge on the 6TB of PCIe attached solid state storage per BackBlaze pod for over a million IOPs over 10Gig E. If you need high IOPS and big storage you can use adaptor brackets and 2.5" SSDs or mix in an array of The Collossus, though you're reaching for a $6K/TB price point there and cutting density in half but then the SSD performance SAN has an equal multiple and some serious capacity problems. If you go with the SSD drives you would want to cut down the SAS expanders to five drives per 4x SAS link because those bad boys can almost saturate a 3Gbps link while normal consumer SATA drives you can multiply 3:1.

If you're more compute focused then a BackBlaze node with fewer drives and a dual-quad motherboard with 4 GPGPUs is a better answer. At the high end you're paying almost as much for the network switches as you are for the media. If you're into the multipath SAS thing then buy 2x the controllers and buy the right backplanes for that - but

Check out Intel D945GSEJT Johnstown Mainboard Dual core Atom, low power fanless, doesn't need power supply (jack in back goes right to power brick) and gig ethernet for about $118. Very low profile Mini-ITX board, works well in $39 mini-case. I've been using this combination for all sorts of things esp storage servers ( Try OpenFiler Linux-based or FreeNAS BSD-based FOSS NAS solutions )

It works. It's iSCSI + CIFS / Windows share. It has clustering and block replication. It's open source and support is available. Support is per server - unlimited sockets and storage - so you could really work them with a few hundred PB on a pair of 8 socket/32 core servers. I don't work for them, but they rock!

They're geeks. If you bribe them properly they might come up with a proprietary block level dedupe solution for you.

You've got low latency and high bandwidth. Make your storage iSCSI OpenFiler configured in cluster mode with block replication. Do use a pair of the BackBlaze boxes somebody else mentioned. Configure with RAID 6. Get enterprise support here. You're in and done at $16K capital cost, $2k labor, and annual support (24/7 4 hour response) at $6200/yr for 67TB of raw storage (~48TB net) plus whatever the network, rackspace and power costs, and it scales in volume storage at linear cost when your needs do and the more volume you have, the better performance gets. As a bonus it fits in two 4U slots.

If you want to skimp you don't have to fully populate the boxes until you need the room and can save $8K in capital costs up front. Every couple of months you have to hot-swap out some cheapo consumer grade drives so buy a few spares and configure them as hot spares and a few more for cold spares. If you have some extra Franklins, splurge on the 10G Ethernet connection from the BackBlaze box to the local network - the remote can stay on Gig-E because it's only used for writes or HA. With a little mental gymnastics and PSU field modifications you can use one BackBlaze master to control up to three BackBlaze slaves with passthrough connections only - no internal server needed. Just get the cards with some external eSATA or external SAS ports, depending on your preference. You might need to upgrade the motherboard spec on the master BackBlaze box, but it's worth the extra money. Since Openfiler support is unlimited CPU you may as well get the dual quad core Nehalem motherboard with 72GB RAM and 8 PCIe slots, or whatever's in the sweet spot this week. I do like the X5550, but if you can get a quad core for under $100 it's hard to pass up, especially combined with one of these cheap motherboards that use up to 32GB of cheap DDR2 RAM. Be careful with your PCIe slot counts when choosing motherboards.

Configure whatever machine you're using to do a backup periodically from one i-SCSI LUN on the local machine to another LUN. This gives you protection against 90% of backup needs (oops! I accidentally all all my presentations!) and will be transparently replicated to the HA site at block level without user intervention. Somewhere in here you should educate users that backup systems are not an alternative method of version control.

You could probably upgrade this with a few TB of PCIe attached SSD cache (pdf) for the million plus IOPS, guaranteed multiple 10Gbps network port saturation for an additional $40k, if you knew how, or why, or needed to.

Or you can go cheap with Linux and BSD and some scripts. You won't save any money and you won't have support. Buy the support. It's worth the money. Disclosure: I don't work for any of these folks. For the company I work for I can quote you a FC SAN. Trust me, you don't want to know what that costs for 67TB with block replication to a DR site and 24/7 4 hour support, let alone the scalable solution I've proposed here. Just assume it's "a lot".

The Backblaze hardware setup looks impressive and might be worth a look. As for software how about something like openfiler http://www.openfiler.com/ If those 2 could be combined it would make one impressive setup.

Of course it can. So can Linux. Naturally if you use Linux you can run all the incidences of Linux you want without paying extra. That'll be handy when we get to that many cores because lots of useful new software is coming out as virtual appliances - like OpenFiler.

Now... What are you going to do with those threads? Run every Explorer tab in a separate VM? How many incidences of W7 do you need on one workstation? How many incidences of W7 can you run on that SuperDome box for the base price? Hm? And when that's a $5k desktop workstation machine what's that going to cost? Is the W7 virtualization cross-platorm? By cross platform I don't mean "All the version of Windows and Microsoft's lapdog Novell's toxic SLED." I mean everything. Well?

The W7 Extreme Signature Racing Stripe Edition might as well be their 3-app limited crippleware on the kind of iron that's landing this year and next. Last time they missed the turn thinking the minimum was higher than it was. This time they miss thinking the maximum was smaller than it is. Poor Microsoft. Their software just isn't flexible enough to scale.

There are many open source nas implementations available: FreeNAS OpenFiler and NASLite to name a few. I have personnaly set up 3 different NASLite boxes, and is the one I recommend for stability and simplicity (It is not free, but reasonable--around $35US). You will, however need to connect the laptop to a monitor for initial installation and setup.

Never underestimate the bandwidth of a station wagon full of backup tapes. Or, in modern terms, NAS. Nothing replaces the obvious answer: Lend your NAS to a friend with equal quality standards for a few days, and let nature take its course. If that friend doesn't have your rip, back up the NAS to your media center and repeat until all your friends have offsite backups of each other's valuable media for disaster recovery purposes and you have what you want.

Not that I would advocate watching the backups of DVD's that you don't have purchased media for... oh, no. That would be immoral. Not quite as immoral as charging $16 bucks for Waterworld: Director's Cut or Glitter [4:3], but immoral still.

After all these years why are we even having this talk? Kids these days. /lawn, onion, etc.

Since I'm already offtopic, I might as well go whole hog: using an old computer, the free OpenFiler app and a 4 port ESATA card you can turn 4 of these NAS+eSATA devices into RAIN: a Redundant Array of Independent NAS, for 27TB of massively parallel striped redundant hot swappable SATA goodness for about 6 grand served up as iSCSI. If you've been pricing that class of storage in the enterprise lately, you should now be going... wait, what did he say? Yes, I did say iSCSI SAN for $250/TB with redundancy, failover, striped performance and a scalable architecture that goes as big as you like. Yes it includes web management, clustering, unlimited snapshots, resizeable LUNs, static and dynamic replication and all the other SAN goodness. Though I'm not quite sure about data dedupe yet, at this rate for raw storage does it matter? Data dedupe is about making the most of that precious investment. If the investment is out of petty cash you don't need that kludge any more than you need Full Disk Compression, RLE, or any of those technologies built to get around the high cost of storage. Of course it runs in Linux, and of course it's available as a virtual machine, and naturally since the software is FREE there's no per-terabyte licensing. The license doesn't expire, run out, require keys or maintenance or accounting, it doesn't require a license server and when the array needs expansion or an upgrade in technology they can't tell you that you have to upgrade to the new version and buy licenses all over again. It's all about knowing what you're doing - a lot of the Top500 use OpenFiler to serve disk to their supercomputers.

The biggest thing that you have to watch out for with VMWare ESXi is the hardware compatibility list. You will run into trouble with two major components: RAID controllers and network adapters.

The network adapter solution is simple: buy the most plain-jane Intel PCI or PCIe adapter that you can find. Examples of ones that are known to work right out of the box are the Intel PWLA8391 GT (single-port PCI) and the Intel EXPI9402PT (dual-port PCIe). I own both of these and can personally confirm operation with the latest version of VMWare ESXi.

The drive controller situation is both complicated and -- more importantly -- expensive. Overall, Adaptec seems to be the most well-supported controller hardware out there. I have tried LSI controllers, but they often don't play well with desktop boards. Unfortunately for experimenters, the built-in RAID on practically every Intel motherboard is completely unsupported in RAID mode. Obviously no enterprise environment would be using on-board RAID like that, but it would be nice to have for experimentation.

Which brings me to my favorite storage solution for ESXi: Openfiler. Openfiler is an open-source NAS/SAN solution based on rPath Linux. It turns any supported PC into a storage applicance, and can share its storage in a plethora of ways. In the case of a virtualization effort, it has two major things going for it: it supports any storage controller that Linux supports, and it supports iSCSI and NFS.

If, say, you do have a machine sitting there with Intel on-board RAID, you can install Openfiler there. While the hardware might not work under ESXi, it'll work great for Openfiler. Even better, Openfiler also supports Linux software RAID which can be superior when it comes to disaster recovery (no need to have a specific controller card to see your data). With this in mind, you'll be able to get Openfiler running on just about any hunk of shit box you have sitting around.

Once you have Openfiler set up, you can take the next step in virtualization-on-the-cheap: installing ESXi on a USB flash drive. There are a number of tutorials on the web for this (just google 'ESXi USB flash install'), but the basic process amounts to extracting the drive image from the ESXi installation archive and simply writing it to flash with dd (on Linux) or physdiskwrite (on Windows). Once this is done, you can plug the flash drive into nearly *any* recent x86 hardware and it will boot ESXi. A really neat feature that you get along with this is the ability to substitute hardware with ease, and upgrade to later versions of ESXi simply by swapping the flash drive.

Once you have ESXi installed, create an iSCSI volume on your Openfiler box. Then, use the VMWare management software to connect the ESXi box to your Openfiler iSCSI volume. You can then create virtual disks and machines from the actual USB-flash-booted VMWare host, all of which will be stored on your Openfiler machine. You may also want to try experimenting with NFS instead of iSCSI. There are a couple proponents of this out there that say under certain circumstances it's even faster than iSCSI. It also makes backing up your virtual machines a little simpler since an NFS share is generally easier to get to than iSCSI from most machines. Another cool aspect of the Openfiler-based configuration is that you will get access to another whiz-bang feature of VMWare called vMotion. Since the VMs and their disks are stored centrally, you can actually move the VM execution from one ESXi box to another - on the fly.

In all, this is a great way to get your feet wet in virtualization because you can have a pretty sophisticated setup with very basic commodity hardware. If you want to go the extra mile and get really fancy, put a dedicated gigabit NIC (or two, bonded) in each box and enable jumbo frames; the SAN will be more than fast enough most anything you'd like to do.

Good luck!

While I agree with your sentiments, actually iSCSI is viable for SOHOs.

I recently re-evaluated our backup strategy and came to the same conclusion as you i.e. generally speaking "enterprise" backup is in a very sorry state. The only modern approach that I liked was iSCSI but of course the Sun, IBM and Dell solutions all cost upwards of $3K.

The cheap (and almost as good) solution I found was to build your own. All you need is another box and http://www.openfiler.com/ - works like a dream.

Instead of FreeNAS, I've tried . I managed to configure an iSCSI target with DRBD as the datastore for my VMware ESX 3.5 server.

OpenFiler is neat and easy to use. Check it out too.

Cheers, Ulli

ESX or ESXi works just fine with a bunch of plain old IDE and SATA controllers...see here for more information.

You can't put virtual machines on an IDE drive, but you can put them on SATA disks with the controllers listed at that link. You don't get RAID on any of them, though, even if they have some sort of RAID available. ESX(i) only officially supports storing VMs on RAID arrays if the disks appear to be SCSI of some sort (including SAS, or SATA on an SAS-capable controller).

You could also use Openfiler to create iSCSI targets that ESXi can use to store VMs, and Openfiler can use any storage that any modern Linux can use, including Linux software RAID. This allows you to have a VMware ESX(i) setup permanently (ESX was available as a free 90-day trial) on some pretty cheap hardware.

OpenFiler is a free, open-source NAS/SAN server which can provide iSCSI targets, fwiw.

Or OpenFiler, also free and open-source, but Linux-based instead of BSD, and also has nice SAN features like iSCSI target support.
http://www.openfiler.com/

I've looked at OpenFiler before, and I'm still confused on one thing: How do you get it to work as a stand-alone NAS? It has four methods of user authentication - and all them require an external server. (For user authentication, you must have one of the following: NIS server, LDAP server, Windows Domain Controller, or a Kerberos server.) http://wwwold.openfiler.com/docs/manual/#d0e93

I personally don't use Samba for anything, like your cleaning lady, I don't do Windows, but I've at least tested it and seems to work fine. LDAP is supported as well as NT4 and Active Directory for authentication. I have 4 boxes setup using LDAP and backup 300 servers between them and I simply never have to do anything except define new shares when I need one.

If you're after something more advanced than a bog standard cheapo NAS box, maybe Openfiler would be what you're looking for. It's quite a bit more capable than a cheapo NAS or WHS, but at least it's web manageable.

You can try FreeNAS or Open Filer.

See also OpenFiler for another option. Linux based, has a slightly different feature set. Supports snapshots, ldap and kerberos auth, which FreeNAS seems to be missing at this time (unless I missed something or the wiki is outdated). Doubtless missing a few things FreeNAS has; e.g. AFS.

I think you need one of these to install in that old beige box or if you crave a complete solution, one of these.

And let's not forget openfiler, since we're mentioning free NAS solutions. It's not lightweight, but it looks pretty cool.

But how is this better than a Linux or BSD based solution that's free?

http://www.openfiler.com/docs/install/graphical_install.html

Certainly doesn't look too hard. I can't imagine this taking more than half an hour to get working.

So I built a debian box (after looking at FreeNAS and OpenFiler and concluding that they were inadequate for the hardware I had already bought ...).

I used: SilverStone GD01 case (it has room for 7 HDs and big, quiet fans), an Asus AM2 board with 6 SATAII connectors and 2 x gigabit ethernet, I installed a low power Athlon X2 BE-2350 and 2GB RAM as well as 6 Seagate SATA disks with 250GB each. I partitioned the disks to contain a small (2G) partition for RAID-1 and swap (2 x RAID-1 for the root/boot fs - Linux can't boot from software RAID 5 yet, 4 x swap partitions) and the rest of the disk is used for a 5+1 disk RAID-5 setup.

Performance is very good, I can saturate at least the gigabit ethernet LAN connection of my desktop PC both at reading and writing (it chokes at 44MB/s - local speeds are much higher, mail me if you want a benchmark run) and I can also run various server stuff on the box that a normal NAS wouldn't support. The box is extremely quiet, so I'm very pleased.

Buy a couple of 500 GB SATA HDDs. You can build a box with a SATA RAID controller for probably ~$200 or so and throw OpenFiler on it. You still won't do this under $500, though. Probably under $750, though, for sure, if you're careful.

As for the botched MBR, boot an MS-DOS or even a FreeDOS boot disk and do a fdisk /mbr. That should fix it.

OpenFiler.

Fantastic piece of kit.

Besides, F/OSS systems still have quirks. For example, I deployed OpenFiler a couple of weeks ago, and I can't access it by its DNS name (\\foo\bar) but can if I use the IP address (\\10.0.0.201\bar). DNS itself works fine (can dig and ping.) I did some RTFM and Googling and found that the issue may be in the Kerberos library that needs to be upgraded by compiling from source... Clearly I'm not going to do that on a NAS appliance that is supposed to just work. A Windows server has no such issue, it just works. Anyone but a geek would just throw the OpenFiler out because the issues involved (Kerberos, WINS, time syncronization (NTP) etc.) are just way above the pay grade of an average technician.

I used to use gentoo for everything; it's sweet inasmuch as you can do anything with the time. The problem with Gentoo is that it has a HUGE up-front time investment to learn. I'm too old and have too many kids now to keep making that investment. There are good alternatives here and here if you want something easier to use with good management tools. If you want a little bit more, look at smeserver. I seem to recall that there are one or two more like smeserver, but I'm too lazy to look.

Good luck.

Consolidate your multimedia and run MythTV for a while. Once you rip and encode several TV series, all your DVD films, and have the Myth recording your favourite shows, a terabyte doesnt seem that much. If you want an idea for future examples of massive storage consumptions, imagine having MythTV recording all channels all the time, so you'd basically be able to decide post-transmission what you want to view and save...

Of course, while I agree most NAS and SAN solutions are grotesquely overpriced and mainly useful for separating fools from their money, I cant really see why one would bring up ZFS and OpenSolaris for this purpose. Something like Openfiler would be vastly more appropriate, proven and easy to manage.

This doesn't strike me as having much to do with ZFS at all. You've been able to do a home grown NAS / SAN box for years on the cheap using commodity equipment. Take ZFS out of the picture and you just need to use a hardware raid controller or a block level RAID (like dmraid on Linux or geom on FreeBSD). There are even canned solutions for this, like OpenFiler.

That being said, this sort of solution may or may not be appropriate, depending on site needs. Sometimes support is worth it.

You're also grossly overestimating the cost of an entry-level iSCSI SAN solution. Even going with EMC, hardly the cheapest of vendors, you can pick up a 6TB solution for about $15k, not $50k. Go with a second tier vendor and you can cut that number in half.

Don't get me wrong, I've met enough problems myself in IT. But firstly, your problem needs to be expressed clearly.

"High Availability" can mean a lot of things. The most important part of it, though, is "how highly available do you need?". Do you want to survive the loss of a server? Of a room? An office? A city?

Basically, you've got two options.

1. Homebuilt, possibly based around either Solaris (ZFS looks interesting) or a specialised Linux distribution. OpenFiler looks interesting but doesn't appear to get a lot of attention, so community support may be lacking. Unless you've already got the hardware, however, you'll need at least two reasonably large servers.

Depending on how crucial all this is to your employer (I'm assuming it's fairly crucial or you wouldn't be looking at HA systems in the first place), the level of support you have available to fall back on with this may or may not be acceptable.

In any case, if you're going to have to spend the amount of money involved in buying two large servers and paying for support on a linux distro anyway, you may as well look at option 2.

2. An entry-level SAN.

Yes, I know you said you can't afford it. But I don't think the problem you're discussing can be easily tackled for zero-cost, and if there's cost involved you'd be in remiss of your duties to not cover every possible base.

I was faced with the same problem myself a few months ago. Eventually I concluded that there simply wasn't the business justification for highly-available storage - we could make do with servers with redundant power supplies and disks, and regular backups. However, I was surprised to find that an entry-level SAN from Dell (actually rebranded EMC units) isn't that much dearer than "buy two dirty great servers and run OpenFiler", and has the benefit that if you do need support, you don't run the risk of hardware and software support folks pointing the finger at each other, saying "it's not our problem, it's theirs".

Plus any half-decent SAN vendor will provide a clear upgrade path - if you roll your own, you'll have to figure out how you upgrade on your own when the time comes.

Finally, think of it like this.

Any business which relies on its backend systems to be solid and reliable should take any reasonable suggestion to maintain that reliability seriously. And by definition, this implies that storage must be reliable.

If it's that important to the business that your systems continue to operate in the face of extreme adversity, and you decided to save £1000 by taking the homebrew route, you're going to have a lot of justifying to do if the worst happens and your supposedly-HA system falls over. Particularly if your answer to "what are you doing about it?" is "I've posted a message to a forum and I'm awaiting a reply". Realistically the only way it can work is if you're competent enough to be able to fix even the worst outage yourself with little or no recourse to asking on forums (though reading documentation is OK). Even then, you should keep the system simple enough that it doesn't take several months of familiarising yourself with it before anyone else has a chance of fixing it, otherwise all you've done is moved the point of failure from the hardware to yourself.

The alternative answer "I've placed an emergency support call with our suppliers and they should be ringing me back within the hour" carries a heck of a lot more weight.

It doesn't have to be rackmount, if you don't have the space. Instead of the rackmount Travla C146 cases, check out the Travla C134 (http://www.mini-itx.com/store/images/c134-black.j pg) or C137 (http://www.mini-itx.com/store/images/c137-black.j pg) cases, they're really small.

As for setting up the necessary software, there's a number of projects that scratch that itch:
http://www.collax.com/en/resources/download-cbs.ht ml
http://www.openfiler.com/
http://www.freenas.org/
http://www.skolelinux.org/portal/index_html
http://www.ubuntu.com/server

All of these are really easy to install and work exceptionally well.

Very nice and based on my favorite distro as well CentOS.

However, for someone posting with such a low UID, I would have expected a link. Your /. user card is in serious jeopardy of being revoked :)

You're wrong in saying that it needs a base CentOS distribution and then installs on top of it. Openfiler is a standalone installable distribution. Please read about Openfiler's features and please decide for yourself how FreeNAS compares to it. I'm not saying FreeNAS doesn't have a market (the home market).. however you should be careful comparing cars and buses.

Naslite sucks compared to Openfiler. This is why Naslite tries to siphon off Openfiler search traffic by placing ads on google on searches related to Openfiler. Too bad that users who search for what they want know better. Naslite is a closed product and is by far inferior to Openfiler's features.

1. Many solutions did not support and RAID 2. Closed-source meant no ability to hack/upgrade hardware 3. In some cases, inablility to upgrade disk size.

My solution was to build a PC with 2 SATA disks and install SME http://contribs.org/. I wanted the additional benefits of a NT domain controller with roaming profiles and a VPN endpoint, but these were just added benefits to the file service. Under the hood, its just a suite a packages sitting on CentOS. The 2 drives are mirrored using LVM (which was sufficient for my needs). You still retain 'root' access to the host but can manage most tasks from a webpage. I find it to be a near-zero maintance appliance after the fairly quick & painless install.

Another solution that I look at was OpenFiler http://www.openfiler.com/ which also appeared to have good file service (including snapshot capabilities). I decided on SME purely because of the 'extras'.