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Two drive RAID 1 mirroring is good. We've had a lot of trouble recently getting tech support from Promise Technology, so we have switched to HighPoint RocketRAID 133 adapter cards.

These RAID cards use the main CPU, they don't have on-board microprocessors. This causes some problems in Windows XP when you have a script that runs at startup. Some commands in the script will sometimes cause the mirror to break, apparently. Apparently Microsoft has not integrated some of the CLI commands into Windows XP yet. This was such a big problem that I wrote a paper on it for Microsoft technical support: Windows XP problems: Port Re-direction.

If you are willing to spend a little more, a lot of people suggest 3Ware products: 7006-2 adapter cards, for example. We have no experience with them. They have a drawback, compared to HighPoint cards: They won't boot with just one drive, according to 3Ware technical support. After the drives are used in a mirror, they will not boot from the IDE adapter on the motherboard. This could be a big drawback if your 3Ware card is not working for some reason. Possibly 3Ware cards available in the future will not be incompatible, leaving you no way to get your data from the drives. If the card fails, you will at least have to buy another one to be able to see your data.

The advantage with 3Ware cards is that there is a CPU on the adapter, leaving no way for MS bugs to cause the mirror to break. That system is also faster, of course.

I wrote a Slashdot article about RAID 1: Mirroring Controllers - What have been Your Experiences?. Note that the Slashdot software has a bug that will not let you see all the comments in nested mode. That bug is years old.

Slashdot has run a number of articles from people who wrestle with the data reliability problem.

Acronis makes backup software that has been generally good for us. It is possible to do a full hard disk backup of a Windows XP hard drive while Windows XP is running. (This uses XP's Shadow Copy mode.

Slashdot also published a story I wrote about drive imaging software: Experiences w/ Drive Imaging Software?. Best sentence: "Microsoft Windows 2000 and Windows XP have crippled file systems. The file system cannot copy some of the files that are necessary to the operating system. If you don't have experience with Microsoft operating systems, you may find this amazing..."

Windows XP keeps most of its settings in files collectively called the registry. So, no backup is complete unless you back up everything on the boot drive. MS tech support has told me many times that there is no way to do this with Microsoft tools. The recommend a "third party" method. We've tried the third party methods, and had a lot of grief with everthing except Acronis. Symantec has given us poor and unfriendly technical support, in my opinion. Symantec bought its competitor PowerQuest; I view that as a bad sign.

It is really, really miserable for me that Microsoft treats me, and every customer, as a criminal by building in copy protection that mixes all the programs and settings together; the copy protection causes me a lot of grief, and significantly damages the entire design of the OS. Linux is a very strong competitor in that area. Everyone is a friend of Linux, users are not criminals, and the OS design is not degra

I'm currently running a 3 drive RAID 5. It was pretty easy to get going. It all depends on how much you want to spend and what you want to do with the server. RAID 5 gives you (N - 1)*(drive size) storage (3 x 200GB drives gives you 400 GB storage). The problem with RAID 5 is it requires at least 3 drives, the more the better. I really like my 3ware sata raid card, it gives you the option to have "hot spares" so should it detect a problem, it will automatically start rebuilding onto the spare. It's also a hardware-based card meaning (among other things) it takes very little from the server to rebuild the drive. 3ware's drivers were easy to get running (even in linux) and it included a monitoring system that can send alert emails should something go wrong. For more information on the 3ware cards, check their new line out here

This isn't for personal use, but if I wanted a RAID at home, I would definitely consider the same setup as this:
I'm using the 3ware 7006-2 on two Linux boxes (Fedora Core 1) and I'm also using one on a Windows 2003 Server as well. All of them are configured with RAID 1 support and I haven't had any issues on any of the machines thus far (knock on wood). I also bought the Vantec EZ-SWAP MRK-102FD Mobile Rack Frame & Carrier for each drive I have in the RAID as well, these things are dirt cheap ($35.00) and are really nice looking with the LCD temperature readout on the front. This setup might be overkill for home use, but it's certainly not terribly expensive either.

I've been using a couple of 3Ware hardware RAID cards in my FreeBSD servers. More expensive than the onboard crap, but Very Nice. Full hardware RAID 0,1,10,5,50, remote control, hot swap, hot spare, email notification on failure, the works.
You can configure your RAID remotely while your server is running. (But always be careful with your boot disc ;-) Or you can install your OS while the RAID is building in the background. Works with Linux & Windows as well, unfortunately not with MacOS X.
But for MacOS X (& linux) geeks, the XRaid RuleZ!

Rainer

You forgot 3ware. They make some very nice and very high performing SATA RAID controllers. They're all hardware RAID and have excellent Linux/FreeBSD support. They're also all 64bit/66MHz PCI compatible.

Using a desktop removable IDE drive bay, you should be able to accomplish what you want.

The only prboblem is the non-plug-n-play nature of these removable drive bays. What I want is a bay that acts almost like the an 8-track drive or the cart-style game consoles: pop out a drive, then pop in a new one -- no screws to mess with and no wires to plug in.

Go to 3Ware

It is really well supported in Linux (and been since a while) as well as in M$. It supports Hot-Swap and Hot-Spare...

• To use hard drives as a sneaker net?
• For backup?
• For building an "unlimited" storage array?

I've recently switched from Debian Linux to FreeBSD 5.2. I was running a pair of RAID-1 arrays off a Highpoint HPT372 RocketRAID 133 controller using Highpoint's rather lackluster, "open source" driver. Of course, contacting them about FreeBSD support greater than 5.0 has yielded nothing useful, so now I am on the hunt for other solutions.

I've come across offerings from 3ware, notably the 7006-2. What caught my eye about this card (well, all of them from 3ware) was that it's actually a hardware-based ATA RAID adapter (where as RAID functionality is implemented in software for most ATA controllers out there). Does this mean that I can use this card without any driver hell? Will a RAID-whatever array simply appear as another /dev/a[dr]* device or is it not that simple? (By the way, I care little about CLI tools for rebuilding the array. I am content to use the card's BIOS to do management.)

Of course, if I can solve the problem with my Highpoint, that'd be useful too. Currently, if I create a RAID-1 array, the two real disks appear as /dev/ad4 and /dev/ad5 but I also get a /dev/ar0 device. However, if I simulate a disk failure, none of the devices appear. It appears to me like FreeBSD indeed supports the RAID functionality of this card out of the box, but a bit of minor tweaking is required.

The bottom line however is I wouldn't mind buying a a RAID adapter with functionality implemented in hardware. That'd be better overall. I just want to make sure it'll work with flying colors in whatever OS I choose to use.

Just remember, Hardware really runs Software.....

See 3Ware's support notice for this week:

IMPORTANT NOTES:
Available for immediate download:
7.6.4 firmware update to address a compatibility issue with Intel E75xx (Xeon), AMD 760MPX (Athlon) and AMD 8000 (Opteron) series chipsets. For detailed information, please refer to 3ware Customer Advisory. Users are strongly encouraged to update to Software 7.6.4 to avoid any potential compatibility issues.

Compatibility issues means Data Loss....

Maybe I'm just really bitter. Haven't given software RAID a go for a couple of years now. For good hardware IDE RAID 5 under Linux (or other OSs), go with 3Ware's cards.

hopefully you're not actually putting them in a rackmount case. It would be much more efficient to rig it up where they are just bare drives out in the open. Sure, it looks like hell, but you should be able to stack almost all of the drives in a single rack with a bad-ass motherboard and with 3 or 4 of these in each of them. You should be able to find a decent dual motherboard with 4 64-bit pci slots on them. That would be (4x12+4) 52 drives per computer. At 300GB per drive, that would be over 15 terabytes per computer. You would still need about 64 of them to get your petabyte, but you should be able to put 8-10 per rack.

my math could be wrong though. Still, if you want it to look pretty, it's probably better to go blow your cash on fancy dells, or get Sun to custom make you a $50mil storage solution.

Pricewatch lists 160 gig drives as costing about $100. Assuming they cost $125 (including shipping, and not from the lowest priced place), 7 drives, giving you 1120 gigs of storage space, would cost you $875.

You will also need a good RAID controller. 3ware makes the best IDE RAID controllers. An Escalade 7506-8 would be good here.

I use 3ware cards and like them. The drivers are GPL unlike the Promise controllers which, if I recall correctly, are binary only.

The purpose of a raid card is improved reliability. Thus, you shouldn't try to cut corners on quality control to save a few bucks. After all, you're already springing for two drives.

I have had very pleasant experiences with 3ware controllers, both under linux and Win32. Currently I have a 6400 running under Suse 7.3, and three 7400s running under RedHat 8. With some hotswap drive bays, you can even unplug a drive with the system running.

They might cost a little more, but they're widely used under more grueling conditions than the more dirt cheap designs. Also, if you're simply doing raid 1, you can use one of their previous generation cards with no performance penalty, and save a bunch of bucks.

Can you spell 3ware?
They do more than just mirroring, and aren't cheap, but if you wants the quality, you gots ta pay the piper.

Drivers are in the Linux kernel, and have been for some time. ATA or S-ATA versions available.

look

That's all I'm sayin...

Or why not get yourself a few of those neato caddies that hold a HDD, and allow you to swap them out (internally; I am not talking about external enclosures) they are available for IDE, and the more expensive ones (claim to) allow hot swapping, even (I cannot personally verify how well the hot swap feature works or doesn't ...). I have seen them that even allow you to lock them in place with a key; how cool is that?

Much cheaper in the long run, in terms of media costs, at least for large quantities of data. Especially if you score some inexpensive smaller drives (like a surplus batch of 10 GB or so)

Hell, if you went all the way and just put an inexpensive RAID controller in there, it might pay off in the simplification of your backup procedures ... i.e. just pull a drive, and put a fresh one in, let the card rebuild it for you; backup your whole system if you like. Restoring doesn't get much easier than that, either.

Here is one made by 3ware
Here is one made by Promise
There are plenty of other, cheaper ones out there, too

I'd rather buy a proper IDE RAID (not some software based HighPoint-RAID you find on mobos these days) for $300, 8 drives (4 active, 4 hot spares). That's about 160 GB fully redundant drive space for you for $1000.

Alternatively I might buy storage space from a reliable hosting company (any suggestions?) and backup my stuff over the network.

Try this for SCSI emulatin' IDE RAID

SuperMicro has some astonishing cases ( one takes, with their 5-drive backplane-type things, S-ATA, 15 drives .. Stock!! )...

a pair of 3ware S-ATA cards in a dual-Athlon 'board ( cheapest AthlonMP chips you can get, you'd want 'em for unstoppability, rather than for blitz-performance, eh? ... or go for a pair of the slowest, coolest-running, AthlonXP's and short the correct bridges to MP 'em, though the kernel will run as "License Tainted" then... )...

A batch of Maxtor DiamondMax 9 S-ATA drives Model Numbers Table ( plus spares, and check for the prices you want on PriceWatch ), and one could even bolt one onto the side of the chassis ( drill holes for mounting it on, to get the magic 16-drives )

then use RAID-55

3- or 4-drives == 1 RAID5 unit ( within the 3ware card )
2 of those RAID5 units within each 3ware card
4 such units visible to the kernel, which can therefore give you kernel-raid5 on top of the 3ware RAID, so it'd take multiple-drive failure to kill the redundancy of the array.

( yeah, so it'd be a nuisance to have to hot-plug replace the one screwed onto the side-panel, but just arrange that only the other drives fail, right? Simple!
+: )

Be wary of the Enermax P/S's, though, yes they've got an 800w ( or thereabouts ), but I've read that when fully loaded, they don't supply the proper voltages ( Danish review was it? actual tests, they did, but I don't know if they were de-rating for the 'combined' rails that each are rated to a certain current, but their combined rating isn't the sum... all P/S's are done that way... )

Enermax's, though, are as nearly silent as makes-no-difference when loaded to 50%, though, so that's where I want 'em.

Gigabitten Ethernets would make your place cozier, too, rather than all that burningwire stuff....
( though I gather that there are firewire-to-ethernet translation devices 'round... )

PS... that thing-on-my-head ( in me self-portrait ) was supposed to be a Klutz Propeller Beanie, but it seems they don't make one, now, so now it's only a simulation of one, see...

SuperMicro has some astonishing cases ( one takes, with their 5-drive backplane-type things, S-ATA, 15 drives .. Stock!! )...

a pair of 3ware S-ATA cards in a dual-Athlon 'board ( cheapest AthlonMP chips you can get, you'd want 'em for unstoppability, rather than for blitz-performance, eh? ... or go for a pair of the slowest, coolest-running, AthlonXP's and short the correct bridges to MP 'em, though the kernel will run as "License Tainted" then... )...

A batch of Maxtor DiamondMax 9 S-ATA drives Model Numbers Table ( plus spares, and check for the prices you want on PriceWatch ), and one could even bolt one onto the side of the chassis ( drill holes for mounting it on, to get the magic 16-drives )

then use RAID-55

3- or 4-drives == 1 RAID5 unit ( within the 3ware card )
2 of those RAID5 units within each 3ware card
4 such units visible to the kernel, which can therefore give you kernel-raid5 on top of the 3ware RAID, so it'd take multiple-drive failure to kill the redundancy of the array.

( yeah, so it'd be a nuisance to have to hot-plug replace the one screwed onto the side-panel, but just arrange that only the other drives fail, right? Simple!
+: )

Be wary of the Enermax P/S's, though, yes they've got an 800w ( or thereabouts ), but I've read that when fully loaded, they don't supply the proper voltages ( Danish review was it? actual tests, they did, but I don't know if they were de-rating for the 'combined' rails that each are rated to a certain current, but their combined rating isn't the sum... all P/S's are done that way... )

Enermax's, though, are as nearly silent as makes-no-difference when loaded to 50%, though, so that's where I want 'em.

Gigabitten Ethernets would make your place cozier, too, rather than all that burningwire stuff....
( though I gather that there are firewire-to-ethernet translation devices 'round... )

PS... that thing-on-my-head ( in me self-portrait ) was supposed to be a Klutz Propeller Beanie, but it seems they don't make one, now, so now it's only a simulation of one, see...

Have you taken a look at 3ware ?
They make RAID controllers with RAID5 support, all based on ATA-IDE drives, the biggest controller supporting up to 12 drives.
They also support hotswap and all the other goodies you'd expect of a SCSI-RAID-system, but at the price of IDE ;-). (NO I do NOT work for them, nor do I resell them, just another happy customer).
There's hardware support for win/linux/freebsd (Not sure about Mac, but I've tried it under the 3 mentioned and it worked like a charm).

3ware has 8500 series 4, 8 and 12 channel SATA RAID controllers. Maxtor has DiamondMax 9+ SATA drives at 60-200GB. Based on a quick look around the web, they appear to be available now.

You are just being silly now. You are going to need slots to plug these controllers into. It's hard to find boards with more then 5 or 6 PCI slots. You have to start using PCI to PCI bridges on a board once you get over 3 or 4 slots and performance would suffer. There are some nice server boards out there that might come closer to this.

Maybe you need better controllers like the 3ware serial ata raid cards They can go up to 12 port on a single controller.

Which is why I ended up paying extra and getting a nice 3Ware ATA RAID controller. GPL'd drivers, looks like a SCSI device to the system, hardware RAID performance, etc. So far I've only tried their 2 disk controller for RAID-1 mirroring but I hope to pick up an 8 disk controller for my multimedia server project in a few weeks. ;-)

1. don't buy an Itanic, if you're going with Opteron for its ultra-fast RAM ( compared with Itanic ) and drastic cost-effectiveness ( ditto ), an Itanic won't show you whether Opteron'd be a good match: the architectures are totally different.

2. RAID storage: don't buy Promise 'raid' cards ( and DON'T do 'raid' 0/1, do RAID-5 ).

Why? ..
1. it ISN'T possible to use S.M.A.R.T. diagnostics in your drives with the Promise ones, at least ( you'll crash the PCI-bus, hanging, fatally, the machine, using Promise chips .. don't know about Highpoint or Adaptec ), and...
2. they oppose Open Source drivers, and coders, for their own products.

Highpoint has only SuSE 7.3-8.0/Redhat-whatever ( IIRC ) drivers for their fast 1520 cards, but if you want compute performance, you want Gentoo... ( and SuSE's been at 8.1 for ages, now... )

Adaptec? I don't know if their cards have the same issues as the Promise/Highpoint, but their cards compete with Promise's, and so probably cut corners in similar ways ( I'd love to see hard data on that point, though )...

3ware are the only cheap ( compared with SCSI ) RAID controllers I know-of, that offer bootable, real, actual, S.M.A.R.T.able RAID on ATA drives.

( I'd stick scads of 120GB IBM 180GXPs on 'em, because they're cooler-running than the 180GB versions, and better than most other drives: fast, quiet, reliable-looking, etc .. quiet means, to me, that wear&tear isn't happening as much, though I wonder-at the No-Seagate rule expressed earlier... is it that fluid-bearings fail soon? or that Seagate has worthless support from our perspective? )

3. SuSE or Gentoo are really your only choice, that I can see.

Why? .. 1. Redhat's trying to microsoft linux, by ignoring standards and making its way law, and Mandrake's .. a flaky ( though fast ) variant originally based on Redhat... I'm fed-up with both, but YKMV ( metric, here )..
2. SuSE includes damn-near every program-capability one could imagine, and has excellent hardware support ( beyond any others' )..
3. Gentoo's compiled specifically for the hardware you are running, and with --buildpkg you get to build on one, then copy all the tbz2's built, to all of the other ( identical ) machines, and just install 'em, and voilá: ultra-performance.

Misc Links:

Chassis, suitable for lots-of-drives NAS type thing.. or this one for well-cooled system ( thick aluminum's a good conductor of heat, and that makes for a longer-living, less-downtime machine )

I'd use Athlons, but that's just me ( Intel's murdered/crippled WAY too many CPUs, and chipsets, for me to be loyal to them ), and would use these HSFs with Verax.de ( or Panasonic Panaflo ) fans on 'em, just because the noise machines make increase sick-time and reduce health/sanity/productivity so damn much.

Consider using P/Ss like these, remembering that 1. they're REALLY quiet only when running at about 50% load, and 2. the UPS-VA-rating you need for each one is DOUBLE the delivered-watts rating of the P/S.
Also, you want LINE-INTERACTIVE UPSs on all machines. ( NO data-corruption due to brown-outs or other glitches ).

I'd consider dual-CPU machines standard for the desktop, simply because even if a CPU was saturated, on that machine, the machine'd still respond, and I'd stuff as much quick RAM into it as I possibly could ( 3GB/desktop, for engineers ), and I'd ALWAYS use ECC RAM.

Consider this board as something to compare against, with Something Like This KVR266X72C25/1G or this times 3 of 'em, per motherboard.

Like the Marines: Capability-based, not capability-choked, right?

The best advice I've seen on this page is

1. get a GOOD admin ( character, more than anything, values, sanity, cultural-harmony-with-you: you CAN change someone's skillset, you CANNOT change their nature ), and

2. metrics, understanding precisely what 'success' means, what the context is, etc...

3. do it one unit at-a-time

Oh, yeah, here's an Opteron-board news link... ( I'm waiting for lots-of-SATAs-on-board )...

Finally, change the ferro-resonant ballasts in your flourescent lighting to RF ballasts, and switch to Phillips TL-930 4' fluorescent tubes ( Colour Rendition Index of 95, rather than the cheap-cool-white CRI 50!! ), and your health will improve, significantly ( you can then ask for a raise, for your increased effectiveness, see )... if you find the warm-white of the TL-930s ( 3000K ) not brilliant/awakening enough, then mix-in a couple of TL-950s ( 5000K, mid-day-sunshine/sky colour ), to punch-up your alertness.

More info here

Any company that backup important material to tape should either make sure they have a working restore-mechanism in place or continue to move the data to newer media every other year...
That being said, the prices of IDE-harddrives and raid-controllers like these, you might as well keep all your data online. That's a sure way not to let the media become outdated...

The main problem w/ the 3ware 8500's is that they're actually 7500's w/ SATA converters (actually a hair slower due to the conversion overhead), and still PCI 64/33. A whole slew of PCI-X true SATA RAID controllers (one from 3ware is supposed to be out late this quarter) will be coming out in the next few months. Should be interesting.

The sequential transfer rates being quoted are likely RAID 5 for reads. It's not unheard of for modern U320 arrays to top 500MB/s in sequential reads and >20,000 IOPs. (the 3ware 7500-12 clocks in at 190MB/s and ~700 IOPs according to their benchmarks.

(note that PCI 64/33 maxes out at 264MB/s, PCI 64/66 at 528MB/s. With the recent 2.0 specs, PCI-X will take you up to a ridiculous 4.2GB/s)

For major speed, check out this Ram San. 700MB/s bandwidth and 200,000 IOP?!?! Yowza!

AMS DK-035A (ignore the Ultra SCSI reference on that page, the A suffix is for ATA), available for $159 from Central Computer

I just set up an eight drive RAID using one of those, and one 3-drive-in-2-bay version, the DK-023A ($119 from Central Computer). That way eight removable trays fit in my 5-bay 4U rack mount case.

I used a 3ware Escalade 7500-8 RAID card rather than Linux software RAID, but there's no reason why it wouldn't have worked with software RAID. I just couldn't find a "dumb" eight-port ATA-133 card. (And I like the 3ware cards.)

I initially tried to use Serial ATA, using the Promise SATA150-TX4 4-port Serial ATA controller and some Highpoint RocketHead 100 Serial ATA adapters for the drives. The Highpoint web site claims that the RocketHead 100 is not available for sale as a separate product, but lots of retailers including Central Computer seem to have them. The cabling was *much* nicer, but to make the SATA150 work with Linux a binary-only driver was required, so I decided not to use it until there's a driver available in source form.

I thought about using the 3ware Escalade 8500, which is the Serial ATA version of the 7500, but there's quite a price premium, so I decided to stick with parallel ATA for now. Maybe next year I'll set up a bigger RAID using Serial ATA.

AMS DK-035A (ignore the Ultra SCSI reference on that page, the A suffix is for ATA), available for $159 from Central Computer

I just set up an eight drive RAID using one of those, and one 3-drive-in-2-bay version, the DK-023A ($119 from Central Computer). That way eight removable trays fit in my 5-bay 4U rack mount case.

I used a 3ware Escalade 7500-8 RAID card rather than Linux software RAID, but there's no reason why it wouldn't have worked with software RAID. I just couldn't find a "dumb" eight-port ATA-133 card. (And I like the 3ware cards.)

I initially tried to use Serial ATA, using the Promise SATA150-TX4 4-port Serial ATA controller and some Highpoint RocketHead 100 Serial ATA adapters for the drives. The Highpoint web site claims that the RocketHead 100 is not available for sale as a separate product, but lots of retailers including Central Computer seem to have them. The cabling was *much* nicer, but to make the SATA150 work with Linux a binary-only driver was required, so I decided not to use it until there's a driver available in source form.

I thought about using the 3ware Escalade 8500, which is the Serial ATA version of the 7500, but there's quite a price premium, so I decided to stick with parallel ATA for now. Maybe next year I'll set up a bigger RAID using Serial ATA.

You can get a hardware IDE RAID controller from 3Ware right now that supports serial ATA (the model 8500) in 4, 8, and 12 channel varieties or parallel ATA in the same capacities (the 7500 series), and install commodity disk drives. The hardest part about this is getting a chassis with sufficient power and cooling capacity to handle all the drives.

It looks like running 12 Western Digital "Drivezilla" 200GB drives ought to give you somewhere around 2.0TB of storage (taking into account the bullshit mathematics of hard drives). At Pricewatch prices, I see about $3,500.00 tied up in the drives and the controller.

Whoopy shit.

You can get a hardware IDE RAID controller from 3Ware right now that supports serial ATA (the model 8500) in 4, 8, and 12 channel varieties or parallel ATA in the same capacities (the 7500 series), and install commodity disk drives. The hardest part about this is getting a chassis with sufficient power and cooling capacity to handle all the drives.

It looks like running 12 Western Digital "Drivezilla" 200GB drives ought to give you somewhere around 2.0TB of storage (taking into account the bullshit mathematics of hard drives). At Pricewatch prices, I see about $3,500.00 tied up in the drives and the controller.

Whoopy shit.

You can get a hardware IDE RAID controller from 3Ware right now that supports serial ATA (the model 8500) in 4, 8, and 12 channel varieties or parallel ATA in the same capacities (the 7500 series), and install commodity disk drives. The hardest part about this is getting a chassis with sufficient power and cooling capacity to handle all the drives.

It looks like running 12 Western Digital "Drivezilla" 200GB drives ought to give you somewhere around 2.0TB of storage (taking into account the bullshit mathematics of hard drives). At Pricewatch prices, I see about $3,500.00 tied up in the drives and the controller.

Whoopy shit.

Er, no. I've used both, and I am not lying.

One can cost an order of magnitude less than the other, and still performs reasonably well for small servers.

I'm talking about hardware ATA RAID, not that promise or highpoint software raid. I just tested one hardware ATA RAID-1+0 set - 75MB/sec writes, 81MB/sec reads, 640GB online.

I'll grant you this: the performance of "enterprise class" hardware SCSI raid may exceed this, unless you go fibre channel which will definitely exceed this. You may be more concerned with latency than bandwidth, in which case the faster rotational speeds of SCSI drives may be somewhat better for you (thus the point of the original post). And generally, you can cram more SCSI cards in an enterprise class server than ATA cards in a PC.

However, when looking at $50,000 storage solution vs. a $5,000 storage solution with similar reliability and performance for a particular business problem, which would you choose, if you are aren't spending someone else's money?

Plug the 64 bit controller into the 32 bit slot and let the PCI bus be your bottlneck. See their features under minimum system requirements, which specifiy 32 bit or 64 bit. Also, motherboard compatibility, which lists many chipsets without 64 bit pci.

The reason we went with 3ware controllers last time was that we were maxing out the pci bus. Moving to a 64 bit card solved that problem. It's too bad 3ware didn't opt for 66 MHz PCI instead of the wider bus. I wonder how much this has cost them?

Plug the 64 bit controller into the 32 bit slot and let the PCI bus be your bottlneck. See their features under minimum system requirements, which specifiy 32 bit or 64 bit. Also, motherboard compatibility, which lists many chipsets without 64 bit pci.

The reason we went with 3ware controllers last time was that we were maxing out the pci bus. Moving to a 64 bit card solved that problem. It's too bad 3ware didn't opt for 66 MHz PCI instead of the wider bus. I wonder how much this has cost them?

Up until now I've bought only SCSI drives because heavy compiles (which I do a lot) just choke IDE down. I now have a 4 x 60 GB RAID-1 and it just screams. With a one time investment in a proper IDE RAID card with escalator scheduling, tagged queueing and big cache I still save a lot of money by being able to buy large but cheap IDE disks.

Those cheap-o-RAIDs are essentially software RAIDs. Most if not all RAID functions are done by the drivers, not on the card itself.

Entry-level real hardware IDE RAID cards cost approximately $500 - almost the same as a SCSI RAID. That's obviously offset by the cheaper disks, but still...

Enter the conversion.

Adaptec makes a pricey 4-port external SCSI card. That's a total of 14*4 usuable drives on a single bus. SCSI drives ARE expensive and when you have 40 of them, it's way more expensive, even with the converters. I see these converters as an ideal way to built multi-Terrabyte arrays at 3/4 or less of the cost of a SCSI array.

3ware offers a serial ata controller, but no drives. No one else offers any drives yet either. You can get these adapters, but the adapters themselves draw power and the number of power supplies you end up needing gets ridiculous really quickly. Hopefully companies will start offering drives for serial ata "real soon now."

Oops, too late to edit. :P Alternately, you can go IDE. These are 12GB units, and you can hook up 12 per IDE RAID controller, 6 controllers per system, for a total of 864GB per system.

I'd read something about "serial ata" when I was drueling at RAID stuff on 3ware's site but I didn't realize what it was until now...
To me it looks/sounds really cool, and I'd love to get a small raid array of these in my next computer, but has anyone seen any SATA drives on the market?
Dirt Cheap Drives and yahoo shopping show nothing....and no, neither does pricewatch.... I take it these drives don't exist yet? Then why are there RAID cards for them?

Someone please unconfuse me...

1. You can't HOTSWAP an IDE drive without risking blowing your drive, crontroller, or upsetting the powersupply.

With SATA you can.

2. You can't WARMSWAP an IDE drive, without risking blowing your drive, controller, or upsetting your powersupply.

With SATA you can.

3. IDE still only supports 2, yes 2 drivers per controller, which makes it impossible to do hardware RAID-5. That leaves us with software RAID-5 as our only option.

Who cares when you can get hardware RAID-controllers with 12 ports on one card? What is the great advantage of having the cable be the single point of failure for your whole RAID, like SCSI does?

4. IDE cables can only stretch so far, so even if you could somehow manage to get 8 IDE controllers into a box, for a total of 16 drives, there would still be cable length issues. I think 1 m is max. We need differential IDE :)

Ok, 1m can be a problem for some people. However most people do not have cases larger than 1m.

5. IDE drives are just now able to verify data integrity, but thats good since we can start using IDE drives in servers that don't need 100% uptime.

Err, why is it a problem when it is already fixed as you say?

6. ATA/100 Round IDE cables are already available. In fact I just ordered some that have a UV reflective coating for my next case mod which features a black light. Airflow isn't a big issue, in fact Compaq has been slicing up IDE cables for a long time now to increase airflow.

Round IDE-cables are expensive to produce and still large and inflexible. SATA solves it.

7. The SUSTAINED TRANSFER WRITE RATE of IDE drives is still not fast enough to store uncompressed NTSC video at 60 frames per second, or store high bandwidth Satellite streams.

So get the hardware RAID-controller and start streaming away. Oh wait, hardware RAID for SATA doesn't exist. 3ware is a figment of my imagination.

8a. Size increase (GB's) are not keeping pace with read/write access speeds and simply adding cache RAM and tweaking seek algorithms isn't going to remedy this problem.

You can't blame the interface for that. 150MB/s per drive for 12 drives on one card is way more than any SCSI solution supports -- and way more than current drives need.

8b. As, internal volatile write caches grow larger, the risk of uncommitted writes being lost in a power outage or crash increases.

So turn off the write cache. ATA supports Transaction Command Queueing although not all drives support it yet. By the time SATA drives become available, TCQ should be common.

Look at the 3ware website and check out the Escalade 8500 series SerialATA controllers. Up to 12 drives in a RAID5 set, or JBOD, WITH hot swap and removable tray configurations (from some VARs). Yeah, they're brilliant to be sure.

Actually, if you really value your data you'll make backups or at least use a RAID array. 3Ware makes really nice RAID arrays that use IDE drives, and present themselves to the OS as a SCSI drive. You can find these on ebay frequently for under $100.

It doesn't matter what the warranty is. Even the best warranty in the world isn't going to bring back your data.

They are here

You wouldn't speed up a single drive. If you have 2 IDE drives on one cable then they are sharing ata100/133/etc. SCSI controller could give you more overall speed if you have several drives.This could be a nice solution for specific applications.

I'd prefer to buy a 12 drive 3Ware IDE RAID card and be done with it. They are now shipping Serial ATA RAID controllers. Mmmmmm!!

Take a look at 3ware (www.3ware.com). Their controllers cost a little more than the entry level promise ones, but they also walk all over them in terms of features and performance.