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Please remind me not to let you administer my filesystems.

http://jrs-s.net/2015/02/03/will-zfs-and-non-ecc-ram-kill-your-data/

https://forums.freenas.org/index.php?threads/ecc-vs-non-ecc-ram-and-zfs.15449/

https://arstechnica.com/civis/viewtopic.php?f=2&t=1235679&p=26303271#p26303271

https://www.csparks.com/ZFS%20Without%20Tears.html

If you want to get directions to a destination you have to turn on location services on your phone which then sends your location to a server to generate the maps/directions. You have the same problem if you're a runner or cyclist who wants to track their workouts. All of the data is stored and processed somewhere else.

Or you could use an offline maps app like OsmAnd~ and not need to use anything but GPS. (Even works on tablets.)

If you install a messenger/comms app on your phone it wants to read your contacts so you don't have to manually copy the entries over. Who knows what else that app does with the information?

In general, any comms app is a privacy risk because it uses network by design. The question is what does it have access to, not if it will transmit it. The best protection is looking at the code yourself and building it yourself, but few would do that due to the time and skill required to do so. That being said, I would use: Xabber.

If you use a hosted email service they have the ability to read your cleartext messages.

You clearly don't know how email works. ALL email is cleartext, regardless of storage location, unless you encrypt it yourself before sending it. Try using PGP. Is it a pain to set up? Depends on how well your favorite email client supports plugins. K-9 Mail supports encryption so my suggestion is to use it.

If you want your pictures automatically backed up to "the cloud" then the provider can access them.

In general using a "cloud" service really means "potential data mining" service. By definition, you're giving your data to someone else to hold. Unless you encrypt it first, it's going to be viewable to who / what ever you upload it to, and that's true regardless as to what the data is. (Password, Picture, SSN, A spreadsheet, an email, etc.)

That being said, if it's data sync between devices your primarily after, you could set up FreeNAS, or something like ownCloud locally. If it's the offsite storage you are after, compress the data, then encrypt it with something like APG before sending it (or something like AxCrypt for windows.). (More encryption tools for windows: http://lifehacker.com/five-bes...)

They would allow data to flow in from the Internet, but not back out.

They have that already. It's called "TV" and "Radio". The last component (that I didn't quote) already exists too and is called "sneakernet". (See also the recent increasing scrutiny and intrusion of digital devices by government agents if you want to see why that's becoming a less reliable transmission method.) Your idea would make the Internet completely useless as a communications medium for anyone except special interests who could afford being "allowed" to transmit to other devices. Make no mistake about saying that either, that's exactly what the *IAAs of the world want.

Granted the Internet is not secure, (It was never supposed to be. Insecure transmissions is at the heart of it's design and origin.) but there are methods to protect yourself if you choose to use them. They just require you (and others) to learn about them first. Rather than try to reinvent a propaganda machine, how about trying the tools available and teaching others about them instead? It would make everyone better off.

*Sidenote: I assume you are using a phone and not a PC. Most people are moving that way due to them not actually needing a workstation for

So Microsoft finally commented:

We’re confident that as we continue to listen to users and provide updates to the app with new features and functionality, we’ll be able to keep improving the experience.

So the usual marketing blabla of "improving your experience". When, for crying out loud, is a company going to admit that they were wrong and going to reverse course??! Just for once, please. Just say "Oops, sorry. We hear you; here's the previous version." Now that would be really listening to your customers.

FreeNAS did: http://www.freenas.org/blog/freenas-corral-status-release-technology-preview-status/

FreeNAS Community - Friendship Is Magical!! https://forums.freenas.org/ind...

Since you are already running a NAS, you may be interested in ZFS on Linux or FreeNAS for a BSD system as a way to bring ZFS into your mix.

zfs

ZFS is a pretty good solution. Multiple NAS ZFS systems with snapshots and replication are even better.

I personally like XFS in production (including LVM), but ZFS is hard to beat if bitrot is your #1 concern.

Install ZFS on your Linux box.

If you're going to do this for anything other than experimental purposes, be sure you're using ECC RAM. You probably aren't and your current board most likely doesn't support it, so you'll need to get a new motherboard, possibly a new CPU and new RAM.

ZFS does something no other filesystem you’ll have available to you does: it checksums your data, and it checksums the metadata used by ZFS, and it checksums the checksums. If your data is corrupted in memory before it is written, ZFS will happily write (and checksum) the corrupted data. Additionally, ZFS has no pre-mount consistency checker or tool that can repair filesystem damage. [...] If a non-ECC memory module goes haywire, it can cause irreparable damage to your ZFS pool that can cause complete loss of the storage.

A Complete Guide to FreeNAS Hardware Design, Part I: Purpose and Best Practices

Which is why I have a whole house DNS server that redirects to a catchall Nginx server that returns a 204.

This article suggests that ECC should be used more than it is. Since yes, a single bit error won't matter at all to an MP3 or a moviefile, single bit errors can ruin JPEG files pretty easily, or corrupt a Word document. The point is you don't get to choose where the error will occur, so you have to assume it will happen in the worst possible place. There is a reason ZFS systems should have ECC memory.

It is not difficult to setup http://www.freenas.org/ on a small server machine, and benefit from FreeBSD security with no (known) backdoor accounts. If you're really serious get a proper NAS motherboard with ECC RAM (if you're not using ECC RAM, then it means you're not very serious with your data anyways), which won't cost you more than $500 with the case and the PSU.

Of course if you're unable or unwilling to secure your box, accept that anything on the Internet is wide open, and buy (rent) online storage from Amazon, Box, or somewhere similar. Amazon gives free unlimited backup account with prime (which is around $99)

First you need to ask yourself some questions:
1. what are you trying to protect against? Hard Drive Failure?, Multiple hard drive failures? Fire? Theft? Disk/file corruption? Destruction of your whole home/work? Everything?
2. what's your budget?
3. how many copies of data do you want and where?
4. If you're looking at a cloud backup service then what's your bandwidth? How much of your internet usage are you happy to allocate to backups? how much is your data change rate? (i.e no sense using a cloud backup provider if you change your data faster than you can upload it)

Some options:
1. Cloud Backup service (e.g. Backblaze, many here)
2. Cloud Storage provider (e.g. Dropbox, Amazon Glacier)
3. Your own solution (e.g. FreeNAS, external usb drive, eSATA (external SATA) drive, home server, unison, xcopy etc...).

If you do use your own server solution then I'd recommending having a look at ZFS filesystem (e.g. zfsonlinux)

His rant is correct.

For example the issue with not having ECC-RAM: https://forums.freenas.org/ind...

Or the checksumming thing.

Think of having a 20 GB VM-Image. One bit flips. In the unused space inside the VM's filesystem, but who knows this.
Next comes ZFS, detects a wrong checksum and deletes the whole image file (yeah, Host-FS is consistent again!).

Think of having a folder of JPEG files and a lot of bit flips. You would notice it only on very few, where it happens in the Header, the rest would have like one wrong pixel. But ZFS deletes them all.

All file systems are approximately the same for most day to day users.

ZFS is not merely yet another way to arrange pieces of your files on the disks (and "disks") — it is a filesystem and a volume-manager in one.

I would be interested in knowing which is fastest at read/writes.

ZFS adds features, which are a rarity among other filesystems: checksumming, options for redundancy and deduplication, snapshots, etc.

We spent decades keeping the underlying storage separate from the filesystem on top of it — neither ufs, nor xfs, nor ext know, what actual hardware is underneath the /dev/foo — and SCSI or (S)ATA protocols is all they can use to talk to this device. In these days of RAIDs and SSDs, the newfs(8) still has notions of sector-sizes and cylinder-groups, for crying out loud.

With ZFS we have a filesystem, that is aware of the underlying hardware and can make a good use of that knowledge. It is, what Unix filesystem would've been, had we had RAIDs in the seventies... But the above-mentioned checksumming and snapshots as well as redundancy and deduplication options are useful even on with a single drive.

For home users, basically meaningless.

Come, come, even FreeNAS users use ZFS on their systems to protect their content from "bit rot" and hardware failures. Smarter folks have been turning to FreeBSD, which has been offering ZFS for years — and Linux developers started working on porting it to Linux long ago — first as a FUSE-module, and now, finally, as part of the kernel.

I made flow charts for email troubleshooting (I hated Visio so I used a graphical editor instead), I had grids for IRQ/Address settings, I had step by steps for undoing AOL I.P. stack sabotage (how many of you remember that?) Fact was I wrote really good documentation that anyone from teenager to adult could use to troubleshoot the "normal" day to day issues a worker at an ISP faces without making a condescending script. If you used it for reference it was an answer key, if you read every word you often would know why that problem occurred. I'm of the belief understanding an issue is always better than just knowing what the fix is.

That's my personal belief too. The problem however is that anyone capable of reading such a document and understanding it well enough to use it to troubleshoot can get a much better job than tech support hotline drone. Consequently the companies have to choose between hiring one competent techie at $30/hr to man the phone, or four no-skill minimum wage drones to take calls for the same cost. Inevitably they gravitate towards the latter, not just because it's cheaper per head, but because the vast majority of competent techies I know would go insane handling tech support calls 8 hrs/day. Churn rate would be high, and there are a lot more no-skill minimum wage drones out there looking for jobs than competent techs willing to do phone tech support.

So the companies hire drones for their tech support, and the documentation has to be reduced to a level which can be used by them with minimal (or no) training. That means scripts, checklists, and numbered procedures. Stuff someone with no skills could follow to fix most problems without even understanding what the problem is. Basically, your approach to documentation is what hobbles FOSS documentation - a belief that the user should understand how the software works before he has any right to be using it. That's a programmer's thinking. Most of the world doesn't work that way - you don't have to know how a car's engine, transmission, steering, and brakes work in order to drive the car. Is it helpful? Yes. But it's not necessary. So while I personally agree with your approach (I like to understand how stuff that I use works), I don't think it's the right approach for mass-consumer documentation.

At this point I think the better solution is to revise how we think of documentation. A lot of it is written as if were to be printed on dead trees - a one dimensional script which describes the software or system in a linear fashion. That was a physical limitation imposed on us back in the days when we wrote stuff down on paper. Online documentation allows us to transcend that - hyperlinks, searches, troubleshooting wizards, predictive AI which suggests alternative search terms or related terms that might match what you're looking for, etc.

I've seen a few help documents written really well this way (the default Windows help format is really good at incorporating this functionality, though most help documents don't take advantage of it). But most are just a modern version of the one dimensional books of the pre-industrial age, with maybe a few hyperlinks thrown in. I was trying to fix a problem with symbolic links in FreeNAS earlier today, and the documentation is really well-written as FOSS goes. But it's just a glorified one-dimensional book. I couldn't even search it for "symbolic" because it's not in the index and the documentation is broken up into multiple web pages. The documentation shouldn't be just a straight data dump of everything the software does (worse yet, a one-dimensional data dump). It should be structured and designed to assist the reader in finding the answers he's looking for. Books took the first step in this direction when they added an index and table of contents. With the capabilities of a computer at our disposal, we should be able to write much more functionally useful documentation. If we cared enough to do so.

But if you sync to the cloud, that is, transmit your incriminating video from you registered phone through a cell provider who has your credit card information to a storage provider who also has your credit card information, the cops can show up at your door, follow your car, and get "in your face" until they find something to hang you with.

http://www.freenas.org/downloa...
https://owncloud.org/install/
https://play.google.com/store/...
http://portforward.com/english...
http://www.startssl.com/

Or:
https://www.getsync.com/featur...
https://play.google.com/store/...

Either way, secured, real-time, SSL'd upload to your own server. No cloud vendors, and no credit cards.

You can't easily do much cheaper than the FreeNAS Mini. FreeNAS is not something you throw on an old computer.

The Hardware sticky over at the FreeNAS forums pretty much answers your questions: https://forums.freenas.org/ind...

The cheapest alternative for FreeNAS is probably something along the lines of:
Supermicro X10SLL-F + 8GB ECC DDR3 + Intel G3220 + case and PSU

miniITX would be more expensive, most likely.

100% agree!

If businesses were smart they all would chip in $10 say towards LibreOffice, Inkscape, Krita, FreeNAS, GimpShop, etc.

They could be free of the tyranny of proprietary vendor-lock file formats for once and for all. But yet they would rather pay to suffer ! **shrugs**

Could you image how much development could get done if open source alternatives to X could get funding!? Not say money is a silver bullet TM but it certainly would go a long way!

I'd suggest some further reading.

I would add to you "cons" list that it requires* ECC RAM, though you should probably be using that anyway.

* It's not technically a requirement, but you'll probably be sorry if you don't use it.

No you aren't biased -- it is the average. Ubuntu tends to be used by those new to Linux. :-/ Ubuntu LTS is decent.

At least they _are_ using OS as opposed to Windows.

The experienced sysadmins would be using OpenBSD. Hell even something such as FreeNas.

Do ya'll buy commercial NAS systems, or does anyone here do the FreeNAS type thing as a full custom solution?

I'm running Greyhole on my home server. It aggregates storage across multiple (possibly dissimilar) drives in one or more pools. You can set varying levels of redundancy for each pool; you can have two (or more) copies of documents so that they're safe in case of drive failure, while disabling it for your video library (which is OK if you have it backed up). You can pull a drive out of a Greyhole box and access the files written to it.

I've had a disk fail recently, and another was on its way out (smartctl reported it had no more replacements for bad blocks). In the latter case, migrating data off the old drive onto a new one was easy. The other drive failed outright. My documents and photos were all safe. Some video and music files needed to be restored from backup...a minor pain. Overall, I think it's worked "as advertised" and would recommend it to others.

Do ya'll buy commercial NAS systems, or does anyone here do the FreeNAS type thing as a full custom solution?

Where in the world is serious stuff being done on any of these platforms? Just asking...

Firewall and NAS solutions are often based off of FreeBSD. See, for example, m0n0wall and its derivatives, as well as the popular FreeNAS.

One big advantage of BSD for NAS applications is that it can support ZFS. (Linux attempts have been half-assed, largely due to licensing conflicts.) You really want ZFS if you are building a robust, reliable NAS device.

Some highlights:

• ZFS's design requires RAM to be perfectly reliable, or at least report imperfections. Undetected bitrot in RAM can and will destroy your entire ZFS pool. Thus, a machine with ECC RAM installed is a requirement.
• As if that weren't enough, ZFS eats huge amounts of RAM. The current guideline is 1 GiB of RAM per TB of disk spindles, with 8 GiB as a practical minimum.
• ZFS assumes it has perfect knowledge of disk writes in-flight, and as such doesn't play well with RAID controllers, which can silently re-order writes. If your machine has a RAID controller, the RAID features should be turned off. Don't worry, ZFS has its own RAID features. However:
• Because drive densities are now approaching drive error rates (10**13 bits of storage, with manufacturers quoting uncorrectable errors every 10**14 bits read), ZFS RAID-Z1 is no longer considered sufficient to ensure storage integrity, and you should plan for RAID-Z2 (two parity drives).
• For the same reason as turning off RAID, a "production" FreeNAS/ZFS installation should not be run in a virtual machine. It's okay if you're just test-driving it to get a sense of what it can do, but a live system should run on actual hardware.
• Using ZFS's de-duplication feature is officially discouraged. It may seem like a great idea, but it will gobble all your RAM and return very little benefit. On average, you're better off using compression.

When ZFS dies, it dies in a big and fairly comprehensive way, and ZFS will die if you under-provide it. In any event, you should RTFM before contemplating a build, and know the trade-offs you're getting in to.

Schwab

Some highlights:

• ZFS's design requires RAM to be perfectly reliable, or at least report imperfections. Undetected bitrot in RAM can and will destroy your entire ZFS pool. Thus, a machine with ECC RAM installed is a requirement.
• As if that weren't enough, ZFS eats huge amounts of RAM. The current guideline is 1 GiB of RAM per TB of disk spindles, with 8 GiB as a practical minimum.
• ZFS assumes it has perfect knowledge of disk writes in-flight, and as such doesn't play well with RAID controllers, which can silently re-order writes. If your machine has a RAID controller, the RAID features should be turned off. Don't worry, ZFS has its own RAID features. However:
• Because drive densities are now approaching drive error rates (10**13 bits of storage, with manufacturers quoting uncorrectable errors every 10**14 bits read), ZFS RAID-Z1 is no longer considered sufficient to ensure storage integrity, and you should plan for RAID-Z2 (two parity drives).
• For the same reason as turning off RAID, a "production" FreeNAS/ZFS installation should not be run in a virtual machine. It's okay if you're just test-driving it to get a sense of what it can do, but a live system should run on actual hardware.
• Using ZFS's de-duplication feature is officially discouraged. It may seem like a great idea, but it will gobble all your RAM and return very little benefit. On average, you're better off using compression.

When ZFS dies, it dies in a big and fairly comprehensive way, and ZFS will die if you under-provide it. In any event, you should RTFM before contemplating a build, and know the trade-offs you're getting in to.

Schwab

> I currently have a 2 TB WD Black system drive - what do I replace it with?

You don't. You _augment_ it with an SSD.

OS + Critical (most often used) apps on the SSD. Everything else on the spindles.

The elephant in the room is that SSDs are unreliable so of course everything is backup on a NAS (Network Attached Storage) which you should be doing anyways, right?! I suggest FreeNAS http://www.freenas.org/ which is based on BSD and supports ZFS. Even has a GUI if you don't want to mess around with the command line. Or if you use Linux you can use ZFSonLinux http://zfsonlinux.org/

If you just want to a buy an off the shelf solution that just works Drobo is OK.
http://www.amazon.com/Drobo-Storage-Gigabit-Ethernet-DRDS4A21/

For SSD can personally recommend

* Samsung 840 PRO Series http://www.newegg.com/Product/Product.aspx?Item=N82E16820147193
* Intel 320 or 520 Series http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&Description=intel+ssd

Cheapest SSD prices are < $0.75 / GB. Just wait for them to go on sale (Black Friday, etc.)

I realize the risk of UREs increases with larger drives, but as far as I know this isn't exacerbated with RAID.

You are correct. For example with the WD Red drives I am using, they cite a URE of "<1 per 10^14 bits", which works out to be "less than one per 11.3 TB" (how much less?). At first glance, that doesn't seem like a big deal. That's just a little bit-rot, right? Well, drives are sector-based, so let's say you hit an average of one 4K sector with a URE per 11.3 TB.

In normal RAID-5 operation, the system will be able to correct for that error. However, what happens when you've dropped a drive and are attempting to restripe the array onto a spare/replacement? You need to be able to read all the data on all the remaining drives in order to reconstruct the lost drive. In your case, it appears that would be a total read of 16 TB. It has to read all sectors on the remaining four 4 TB drives because standard, non-RAID-Z arrays are below the filesystem, so the array has no idea whether you are actually using 15 MB or 15 TB of the space your RAID-5 array. While reading in the 16 TB, your remaining HDDs will hit an average of one URE, and now your RAID rebuild has failed by definition. Again, though, who cares if you lose just one stripe in the array per RAID-5 rebuild?

Well, it depends on how your RAID system treats it. If it is programmed to halt the rebuild and mark it as failed, then you are left hoping you can backup all the data and nuke/recreate the array before another drive is lost. At the very least, that would be a significant inconvenience compared to the expected "plug in new drive and wait for rebuild".

Hopefully this 20TB RAID will last like 5 years, and I'll move the data to a new storage system using some better technology that's cheaper, faster, and safer.

I recommend you consider RAID-Z when you are weighing alternatives (haha, obvious plug is obvious). RAID-Z is single parity and so tolerates a single drive failure like RAID-5, RAID-Z2 is double parity like RAID-6, and RAID-Z3 is triple parity.

There are a lot of benefits that RAID-Z offers that can only be achieved by pushing the redundancy considerations into the filesystem, such as only having to read the data in your array that you've actually used when you are attempting to recover from a lost drive (rather than the whole disk). It's also demonstrably safer than RAID-5/6 equivalents, offers simple snapshotting of live volumes to make in-place time machine type backups, the ability to do the equivalent of chkdsk/fsck while the volume is online and accepting RW I/O, allows the addition of SSD cache devices to automatically accelerate the pool, etc. The principal drawbacks today are hardware requirements (performance is best if you have 1GB RAM per TB of disk and a fast, 64-bit CPU) and OS support (though FreeNAS makes RAID-Z effectively painless already and has lots of cool features).

All this isn't to bash RAID-5. I had a hardware-based 4x80GB RAID-5 at home that served me well for over a decade. Then again, when I recently booted up that server to finally offload the data I discovered it had dropped a drive and another refused to enumerate, so the array was toast.

Owncloud is really great. I'd put it on a webhoster so you can reach it from everywhere.
For my home I use a NAS, an old one actually (Siemens AMS150). If you have already decent hardware (lots of drives and a PC) you could try FreeNAS, it does everything a dedicated NAS does and more but of course you won't get the great powersavings of the custom built ones. Setup is trivial and it comes with a HTML-based GUI.
 

It really bothers me that everyone here is propping up all these new proprietary system for something like a backup solution whenever there are so many open alternatives.

Almost anything is better than buying some black box solution that will sure to be outdated and out of the users control in a year.

I use it *without* knowing on my router http://www.pfsense.org/ and my NAS http://www.freenas.org/

Pendantic mode - How do you know you use it without knowing? Besides the boot messages are a dead giveaway.

I used to use pfsense. It worked fine but it did seem annoyingly limited in some respects and everytime I asked how to do a thing I was told I should pay for a bounty to add some feature in the next release. It annoyed me so much I changed to OpenBSD and now write pf rules in vi. Now I know exactly what my firewall is doing, it runs a more recent version of pf, I have way more flexibility to do other things on my firewall if I choose, and pfsense can't compete with OpenBSD's security history.

Silent file corruption is the reason why I now keep all my data on a ZFS filesystem. ZFS has a checksum for every block and if you have redundancy at all (raidz, raidz2, or even just tell ZFS to keep two copies of each file) then it will repair the corruption as well as detect it. I've got a HP Microserver running Solaris but I recommend running FreeNAS instead if you don't know ZFS. This blog is a good place to learn about ZFS.

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.

.
Both FreeBSD and FreeNAS, in addition to OpenSolaris, support ZFS.

http://www.freenas.org/ You can use several inexpensive (and not reliable) disks to be used by the ZFS (software-raid) filesystem. Easy to upgrade/replace/manage. Online storage seems the second best alternative for now , IMHO...

You're wrong.

Get a stable release of FreeNAS on commodity hardware. It will fit the bill for all of the features you are looking for. SMB for Windows clients, NFS for Linux/Unix/BSD, iSCSI targets and initiators, support for several raid cards and drive types, software raid control, several other features. http://freenas.org/

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.

I'll enthusiastically second this. I have been running FreeNAS solidly for 2 months now. I have configured 5 x 1.5TB drives in RAID-Z2 configuration. That gives me 4.01Tb of storage, allowing for two simultaneous drive failures without data loss. My final build uses an ECS 945GCD-M(1.0) Atom 330 Micro ATX board with an Intel 1Gb PCI card; I had a lot of trouble getting the network working with a pure intel board (which did NOT have an Intel network controller on it, GRR). While a highly regarded SATA controller worked with the original Intel MoBo, it didn't with my current one, but a cheaper one does. I'm using a 400MW 80 Plus PSU, and Kill-a-Watt says I pull about 75W total while running, motherboard reports that it's running at about 30C. I have 4Gb of RAM, of which maybe 30% gets used, and CPU seems to be around 10-20% generally. Discounting the hardware that didn't work, it comes to about $1000. I also invested in $130 of UPS (which brought it through a 5 second mini-blackout), and a Gb switch. I get sustained 30-40MB/sec, both to/from Vista and Ubuntu systems over a wired Cat-5e home network; far more than needed for use as a HTPC.

ZFS is stunning. I was sure I was missing something when I set it up but - it's - just - that - easy. It's like encountering a bullet train after spending two decades using hand-drawn sledges to get around. Copy-on-write, self-healing, snapshots as easy as sneezing. RAID configuration that would fit into a Twitter message. Hot spares, automatic re-silvering when adding or removing disks. It's about 4 tech levels above what I'm conversant in, which does make me nervous; I have not tried to recover from a drive failure yet. I'd also like to move the OS off the ancient 30Gb boot drive and onto a flash disk, but want to make sure my tertiary backups (mostly external USB drives) are *really* up-to-date. FreeNAS allows export and import of configuration XML files, so hopefully that will be relatively easy.

I did learn that while you don't need to explicitly format the drives, if you have used them for a prior ZFS system you should wipe them before reusing them. I lost three weekends of my life to trying to configure OpenSolaris (the time would have been better spent getting femur piercings). In the process, I briefly had a four drive ZFS zpool. When I tried to build a pool with those plus one more in FreeNAS, Bad Things Happened. I had to use DBAN to clear off the drives, after which everything went fine. I earlier tried FreeBSD, but it refused to boot from a USB CD with the EliteGroup motherboard. Ah, and I did need to modify vm.kmem_size and vm.kmem_size_max, I think both to 4G. That can be done from the FreeNAS config page (99% of FreeNAS management is done from a webpage, similar to router configuration).

4 of these
http://www.newegg.com/Product/Product.aspx?Item=N82E16822145276 (or whatever your fav is)

1 of these that supports 4 drives
http://computers.shop.ebay.com/Servers-/11211/i.html?_nkw=1u+server&_catref=1&_fln=1&_trksid=p3286.c0.m282

and then install this
http://freenas.org/freenas

$800 4 TB server (raid 10)

I wouldn't limit myself to a certain filesystem, I'd run a dedicated NAS like FreeNAS and share it over the network via SMB (windows), AFP (apple) and whatever for Linux - all set. Plus as mentioned above, you can run Firefly media server, a bittorrent server, a DAAP server (itunes sharing), etc (all included in FreeNAS. http://freenas.org/) on the same box. And since filesystems don't matter in this config, you can use ZFS to make a RAIDZ pool of your drives. It's what I do now.

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 )

The newest FreeNAS RC has support for ZFS and is ideal for backup purposes. The checksumming facility of ZFS also makes you sleep well at night, knowing that silent bit corruption doesn't eat your data. And it has built-in support for rsync.

Exactly what I did with an old one IBM from work with a broken screen

FreeNAS

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.

FreeNas is not supposed to be a production ready product. Note this statement on their site:

http://www.freenas.org/index.php?option=com_openwiki&Itemid=30&id=faqs:en

"FreeNAS is Alpha or Beta, its not a production release and it will have bugs in it. It is your risk if you load valuable data onto FreeNAS."

Why you would risk your customer's data, or recommend that others do the same, is beyond me.

"nstalling Ubuntu or whatever on it seems like more of a performance hit than a properly optimized "off the shelf" NAS box..."

This is true. Take a look at FreeNas. FreeNas is based on FreeBSD and is optimized to run as a NAS server. That is it's only purpose. Works great.

I currently run a small online backup business. I put an external storage device in and connected it to a server running FreeNAS. The data through put to the storage is extremely fast. My main bottle neck is my customers slow SMB or residential internet connection, so my switches are not the fastest and don't really need to be. Where I spent my time and money was the storage. Of course if I need to move the data internally then the switches would need to be looked at. For my situation this works well.

From my limited experiences and what the parent post is looking at, IMHO, to implement a respectable but cost effective SANs, spend the money on enterprise level switches and fast drives, and then save a couple of bucks by implementing FreeNAS connected to an externally attached storage device that contains your fast drives.

A NAS is pretty much a server that is dedicated to storage.

If he wants to roll his own I would suggest either a light install of Ubuntu server or FreeNAS: http://www.freenas.org/. FreeNAS is based on the stripped down Free BSD core that m0n0wall uses. It is very small and is managed using a simple and easy to use web interface. I don't know about gigabit performance as I only set it up once for a friend using 100mbit. He had the Linksys NAS box and it was dog slow. On 100Mb it couldn't push more then 3-4 MB sec. I could get 8-9Mb sec using FreeNAS on an Athlon 1.3Ghz with 128MB ram and two SATA 500GB drives in RAID 1 (mirroring). He also added a USB 2.0 card to hook up another 500GB drive. It pretty much saturates his 100Mbit connection.

And here is my related question to others here:
I have fought with SAMBA on Ubuntu 8.04 server and I cant get it going faster than 10-11MB/sec when copying to/from Windows XP. Even with the tcp_nodelay setting and a few others it just barely breaks 11MB/sec. I can get 25-30MB sec when copying from one Windows PC to another. And the server hardware isn't puny: dual P4 2.4GHz Xeons, 4GB RAM, dual PCIX Intel gigabit and a PCIX SATA controller. Any one have any suggestions? NFS also runs at the same speed and when downloading from the Apache server I get 5-6MB sec. Something is wrong somewhere but I cant tell. I have changed kernels played with conf files but nothing works. Someone once told me SAMBA will always be slow but I don't believe that to be true.

You could always use FreeNAS, which is slightly less complicated and can fit on a USB Key.

FreeNAS is a free NAS (Network-Attached Storage) server, supporting: CIFS (samba), FTP, NFS, AFP, RSYNC, iSCSI protocols, S.M.A.R.T., local user authentication, Software RAID (0,1,5) with a Full WEB configuration interface. FreeNAS takes less than 32MB once installed on Compact Flash, hard drive or USB key.

My home servers are in screaming need of ZFS (A NetApp Filer for home use). I want ZFS implemented in Linux, like everyone else. Moving to a OpenSolaris based distribution just feels awkward and wrong, especially when ZFS has made it into FreeBSD 7.0 as an experimental feature.

I'm eyeballing the FreeNAS project daily. Sooner or later we will have a ZFS appliance, free as in beer at least. Sun have to work harder to win me over but things look promising. (Ubuntu on Sun hardware [+], trying to release Java under an Open Source license [+], closing some MySQL features [-])