Inexpensive solutions for high capacity, 8+ disk RAID arrays??

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InfidelPimp

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Is there anything out there at present that's better than my current approach of an expensive-ish PCI card and a huge full-tower case crammed to capacity with hard drives?

I'm looking to build a new box soon (mainly) because my current RAID5 array is down to its last couple hundred gigs of free space, and I'm hoping to avoid the situation I have now where I've got a dozen drives crammed inside my tower case turning it into a hundred pounds of convection oven that I have to cool with 2 floor fans.

My current array that I'm outgrowing is RAID 5 on an Adaptec 3805 RAID card and eight 750 GB SATAs, all jammed up into a full tower case. Ideally, I'd like to replace it with eight to twelve 2 TB drives, in a sturdy enclosure, which would be connected back to a RAID card in a new, beefy desktop. I'm not opposed to a NAS setup, but all the ones I've seen aimed at consumers are basically useless in my opinion (no RAID 5, 4 drive limit, etc). If I can do it for a couple grand again, that would be outstanding, but with the recent spike in HD prices, 3 or 4 grand would be acceptable.

Anyone here have any thoughts on how to pull this off?

Professionally, I'm used to the Dell PowerVault storage enclosures, which are pretty much what I'm really looking for - a large enclosure (12 drive bays on their current lines, AFAIK), RAID card supporting any meaningful level of RAID (only really care about RAID 5 or 6) and the ability to directly attach the enclosure (and its big-ass array) to your server, or home desktop. Of course, they start at $6,000 for just the enclosure, not including their $1,000 PERC RAID cards and twelve or so $500 enterprise grade, hot-swappable hard drives... and I'm not about to spend 13 grand for what are mostly enterprise-level features I don't need (don't need hot-swappable, or scalability to 60 drives, or redundant PSUs, or the ability to have 100 employees hitting my media library at once, blahblahblah).

Or, for that matter, has anyone had any experience attaching a Dell PowerVault/PERC RAID card to, say, a desktop and getting that to work? That would make ebay and the like a viable option for a used or refurb enterprise-class storage enclosure.
 
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Question I have for you is this, why are you looking at RAID 5? You do realize that going with 8 to 12 2TB drives is going to be a major issue if you ever have a drive fail. RAID 5, at present, is dead if you're running with 8+ drives that are 2+ TB in size because if a drive ever fails, you are guarenteed to get a read error during rebuild which will kill the array (yes, the chance of a read error per bit during rebuild is small, but the number of bits you're reading/writing during a rebuild with 8+ 2+ TB drives is guarenteed to happen, probability of a read error is 100%). This is the reason RAID 6 now exists (2 distributed parity bits instead of 1 as is the case of RAID 5).

If spindle speed is not an issue for you, you might want...

lurkmonkey

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Well, if you're willing to use consumer grade hardware, your budget might allow for something similar to the "backblaze" units. The server and drives are built into a 4 or 5u rackmount case (don't remember the size off the top of my head) and use software raid and port multipliers. Have you considered that yet?
 

InfidelPimp

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Software RAID? No. Not gonna put an array costing a $1000+ in software RAID. Might as well just do JBOD with high capacity disks or buy a bunch of big external USB hard drives, for how reliable that would be.

I was thinking about using a proper consumer-grade enclosure and a high end consumer RAID card like the one I have now... but the cheapest of what I could find seemed to come out to at least $1500... and then why not just do $2000 and buy an older, used enterprise-grade storage array? (Or at least that's how I feel about it.)
 

balister

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Question I have for you is this, why are you looking at RAID 5? You do realize that going with 8 to 12 2TB drives is going to be a major issue if you ever have a drive fail. RAID 5, at present, is dead if you're running with 8+ drives that are 2+ TB in size because if a drive ever fails, you are guarenteed to get a read error during rebuild which will kill the array (yes, the chance of a read error per bit during rebuild is small, but the number of bits you're reading/writing during a rebuild with 8+ 2+ TB drives is guarenteed to happen, probability of a read error is 100%). This is the reason RAID 6 now exists (2 distributed parity bits instead of 1 as is the case of RAID 5).

If spindle speed is not an issue for you, you might want to wait a few more months. WD is coming with a 2 TB 2.5" drive (unsure at this time if it will be 9.5 mm thick or up to 15mm thick). If you are willing, you could stuff a large number of 2.5" drives into a number of cases (I myself am looking at building an array for home use as a lab for running virtual servers) that are actually quite small in size. I'm in wait mode right now for prices to drop and WD and other manufactures to come out with a 2 TB 2 1/2 drive then am looking at using said drives in the following Lian Li case; PC-V354 as this case allows for 7 3.5" drives and 4 2.5" drives (with adapters and 9.5mm thick 2.5" drives, you can get 18 in this case). There are other SFF cases out there, if you look, that do have a lot of space for hard drives especially when you only need a Micro-ATX or smaller MB to host the array.

Right now, I'm looking at about $3500 (at present prices) to be able to put together a system that will have an 8 TB RAID 1+0 array with a 4 port NIC with all ports teamed together to act as a single large pipe for iSCSI. The only downside is I'm looking at 5.4k RPM spindles, so not fast drives, but atleast with 8 in each 0 stripe, should be fast enough for a home lab.

But, there is no way around a good RAID controller that is going to do a large number of drives (I'm looking at $800 just for the RAID controller since it will be using 4 SFF 8087 ports being forward split out into 4 SATAs each (for 16 total drives on the raid controller, other 2 drives will be simply run off the MBs controller for where the O/S and NAS software lives). If you only go with 8 drives, you're still looking at $400+ for a RAID controller (the good ones I've seen are going for around $600).

So, if your present controller card has an SFF 8088 external port, you might be better getting a used enterprise DAS device and hooking that to your system.

Ultimately, it all depends on what you're willing to spend and how compact you want it.
 
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InfidelPimp

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Well, to give you an idea of my data usage, the 8x750 GB RAID 5 array I built almost 4 years ago is basically full. As are both of my scratch disks and my 4 extrenal HDs. It's about 10 TB of data, with more coming all the time.

Since I'm not about to drop the several thousand dollars it would take to get a good tape backup system for my data, RAID 5 is my data redundancy solution. Mirror raid or real backups of that much data is just too expensive. (The really important stuff is in more than one place, but that's about the best I can do without dropping a lot more than I'm willing to pay.)

Unless you have a better idea, of course.



Right, and I'll probably do RAID 6 on my new solution - 4 years back it wasn't available for consumer-grade arrays. Thanks though, I hadn't considered that rebuild issue, so it'll have to be a few RAID5 arrays, or one really big RAID6 array... guessing RAID6 would be cheaper and better.



Yeah, that's how it looks... a couple grand more than I want to spend, but no one seems to have a consumer-grade solution that's going to satisfy my needs.

Right now I'm looking at something"between" these auctions:

http://www.ebay.com/itm/370583280384?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

(Used Dell MD3000, 15x1TB, 5 grand)

And:

http://www.ebay.com/itm/Dell-PowerVault-MD3000-Storage-Array-SAS-15-x-2TB-30TB-/300660390818?pt=COMP_EN_Servers&hash=item4600c17ba2

(Used Dell MD3000, 15x2TB, 10 grand)

I can pick up a really old PowerEdge for free to hook it into. (Like P4, 2GB RAM, Win2k3 STD old... but it should have enough horsepower to serve up the array available on my home LAN, I'd think.)

I think that's probably the best shot I have at doing what I want - a pre-owned PowerVault, with 15 or so drive bays and 1.5 or 2TB drives for about $8000.

You see any problems or issues with that, other than the fact that I'm spending more for a storage array than I did for my car? :lol:
 

balister

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Nope, the MD3000 is good device for what you're wanting to use it for. At my old job, we had one and I was managing it and it did the job we needed it for (used as a back to disk for DPM virtual servers).
 

InfidelPimp

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Looks like I may have been able to pick up an NX3100 on the cheap, and now I just need a dozen 2TB drives to put in it. I don't suppose anyone here knows whether or not I can get away with consumer-grade drives, or if it actually needs the much more expensive nearline-SAS drives?

Or for that matter, where I get a good deal on dozen 2 TB drives for my new NAS server?
 

InfidelPimp

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I did pick up a nice Dell SAS Server for under 3k on eBay, so that's my solution. And since no one could give me an answer on the question about what drives it'll take (Dell support included <grumble>), I'll just give balister the best answer.

Thanks for the help, man.
 
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