What is required for a Raid 5 storage array

[myoung84]

I am considering building a low-cost Raid 5 array for DVD, music, and picture storage. I will not be recording to the array, just storing and playback. I will probably get 5 500GB drives for a total of 2TB of storage. Aside from the drives, what else is required?

I have a spare motherboard with AMD 3000+ single core CPU I can use.
http://www.newegg.com/Product/Produc...82E16813186115
Would this be a usable board for a stand alone storage PC?

What kind of PC cases work best for housing drives? I am new at the whole RAID thing, so not sure exactly what I need.

[Lucas]

It all depends on which OS you want to use.

I suspect that your MOBO does not support RAID5 for 5 disks so you can't use Windows or Linux for Software RAID 5.

That said, you will probably need a 4,6 or 8 port PCI SATA Hardware RAID controller to connect your drives to.

You could opt for NAS software like NASLite which supports some of the older Hardware RAID controllers that can be found fairly cheaply on the net. Then you could choose and buy one of the supported RAID controllers.

[myoung84]

What RAID controller card is recommended? And I will be using XP.

[Shield]

Originally Posted by myoung84

What RAID controller card is recommended? And I will be using XP.

If you're going with SATA, I highly recommend the LSI Logic 8308ELP. Support for RAID 0,1,5,10,50, supports 8 drives, support for write-back cache with Battery backup unit. A slick java based web interface, can boot XP/Vista with it; a true hardware solution.

It's not cheap, but reliable. Bought mine on ebay slightly used for $300 and the BBU was $80 (but it's not really necessary unless you're going to be doing lots of fast writes)

Good luck!

[Sam]

Originally Posted by myoung84

I am considering building a low-cost Raid 5 array for DVD, music, and picture storage. I will not be recording to the array, just storing and playback. I will probably get 5 500GB drives for a total of 2TB of storage. Aside from the drives, what else is required?

It depends on how you want to achieve fault tolerance on your data:

- Hardware based RAID support (generally considered the best, but most expensive)
- Software based RAID
- Dedicated box running something like unRAID ( http://lime-technology.com )
- Snapshot based RAID using FlexRAID ( http://openegg.org/FlexRAID.curi )

The last one looks like it could be interesting for media archives. Unlike traditional RAID approaches, the current release does not provide real time data protection. Instead, you run periodic snapshots to create parity sets over virtually any combination of drives or subsets of drives. For drives that you primarily fill with media content which does not change, this sounds like an intriguing alternative. At least look at the page before you rule it out.

I have not tried it yet, but it is on my to-do list. I don't want to dedicate a box to unRAID, because I'd rather let my server do multiple tasks including Sage, commercial detection, fault tolerant storage, etc.

I also have used PCI cards with Silicon Image chipsets then used SATA port multipliers to let me attach 5 drives per SATA port. Or up to 20 drives per PCI card. But what I don't like is not being able to dynamically add more drives to existing RAID sets.

With unRAID or FlexRAID, you can just keep adding drives as you need more capacity.

Another interesting box is Drobo ( http://www.drobo.com ) but it is limited to 4 drives.

[Shield]

One thing to keep in mind is going with a software Raid 5 solution - if your motherboard dies you can't just throw the "onboard" controller onto another system along with the drives and recover your data. You "may" get an exact motherboard to see the Array, you may not. With a PCI/PCI-X card you can.

It's saved my bacon before...

[stanger89]

It was brought up indirectly Sam, but RAID-5 is a means, not an end. You really should look at what your desired end is, and then you can evaluate the various methods available to achieve that end.

It sounds like your "end" is to have a great deal of storage with redundancy.

Sam also layed out most of the good means to that end, but one other option is a NAS, like a ReadyNAS, Thecus, or Intel.

If you're here, there's a good chance you have, or will have some sort of "server" or PC/system that's probably not directly accessed. If this is the case, then one of the most logical solutions is to add storage to that.

Then the question is how to get redundancy, and at the moment, the most interesting solution is FlexRAID.

RAID, especailly RAID-5 has some compelling benefits, the most so being efficiency. That is you only "sacrifice" one drive's capacity for your redundancy. However RAID-5 has the drawbacks of requiring all drives to be spinning to access the drives, requiring matched drives, and either (expensive) hardware or software (of questionable reliability?), and the data is unusable outside the array.

FlexRAID retains the benefits of efficiency, but without the drawbacks of requiring all disks to be spinning or that they be matched. Also the data can be read outside the array.

That seems like a near ideal solution for something like a media library, where the data does not change quickly/regularly and only small amounts are the data are accessed at any given time.

[mikejaner]

Originally Posted by Shield

One thing to keep in mind is going with a software Raid 5 solution - if your motherboard dies you can't just throw the "onboard" controller onto another system along with the drives and recover your data. You "may" get an exact motherboard to see the Array, you may not. With a PCI/PCI-X card you can.

It's saved my bacon before...

Don't you mean Hardware RAID? If I take my Software RAID 5 array created in Windows Server, and move the disks to another Windows server with completely different hardware, it will see the array.

I think you mean an integrated motherboard based Hardware RAID.

[mikejaner]

Stanger89;
That FlexRAID looks really interesing. Have you played with it yet? I went to get it from the site. Apparently you have to register for the forum, and post to one of the private boards, then wait for him to send you a PM to the link. Waiting on a response from him on that.

[paulbeers]

I guess I will throw this out there, I use Freenas for my RAID 5 array. Its a simple Software RAID 5 and isn't fast by any means (thorough put is about 20MB/s), but it is stable and free. I am using 5 WD 500 AAKS drives to give me a total of 2 TB of storage. All of my drives are hooked to PCI SATA controllers (which is one reason for the fairly slow transfer rate), however, the thoroughput is more than enough to handle playback of my DVD collection....

Freenas server specs:
AMD Athlon64 3000+
MSI K8T800 FSR mobo
1GB DDR400 RAM
GB Ethernet onboard (Realtec I believe)
Basic CD ROM drive
Basic Floppy Drive
5 x WD 500 AAKS drives

Runs flawlessly and haven't had any problems since I built it 6 months ago.

[myoung84]

Originally Posted by paulbeers

I guess I will throw this out there, I use Freenas for my RAID 5 array. Its a simple Software RAID 5 and isn't fast by any means (thorough put is about 20MB/s), but it is stable and free. I am using 5 WD 500 AAKS drives to give me a total of 2 TB of storage. All of my drives are hooked to PCI SATA controllers (which is one reason for the fairly slow transfer rate), however, the thoroughput is more than enough to handle playback of my DVD collection....

Freenas server specs:
AMD Athlon64 3000+
MSI K8T800 FSR mobo
1GB DDR400 RAM
GB Ethernet onboard (Realtec I believe)
Basic CD ROM drive
Basic Floppy Drive
5 x WD 500 AAKS drives

Runs flawlessly and haven't had any problems since I built it 6 months ago.

I notice you have 4 media extenders. Do you have any problems in the rare event you watching 4 separate movies from each extender?

[stanger89]

Originally Posted by mikejaner

Stanger89;
That FlexRAID looks really interesing. Have you played with it yet?

No I haven't, I've got my whole setup "complete" at the moment but full. So I've been keeping an eye out for what I was going to use when I add or rebuild my array. My 8x250GB RAID-5 Array and my 4x500GB "X-RAID" NAS are basically full so I need to do something.

I had always figured I'd go with a nice 3ware SATA card and start populating it with 1TB drives, but as time goes on I keep coming back to the fact that the controller is $400-600 depending on size and I don't need the striping or contiguous array, I just want the redundancy. I like unRAID's solution to redundancy but not it's requirement to be a dedicated PC.

I went to get it from the site. Apparently you have to register for the forum, and post to one of the private boards, then wait for him to send you a PM to the link. Waiting on a response from him on that.

Darn, it used to just be downloadable, hopefully the "final" 1.0 will just be a download.

[Sam]

Originally Posted by stanger89

Darn, it used to just be downloadable, hopefully the "final" 1.0 will just be a download.

When I registered, I had the link emailed to me relatively quickly. And considering I haven't yet taken the time to install and configure it, I'd say the need to preregister was not a big deal (to me).

I guess what I don't like about unRAID or FreeNAS or similar is I don't want to dedicate a box to it -- I'd rather be able to use that horsepower for other tasks too.

What I like about FlexRAID (in theory -- I haven't used it yet) is I can build parity sets over my media drives, and as I grow capacity just increase the number of drives dynamically. Then the drives can spin down independently until one is needed to access data on that drive. For media storage, I really don't need them all spinning all the time, with real-time RAID-5 striping.

And while it would have been my own fault, I had a five 500GB drives in a RAID5 and had one unit fail. Before I got around to replacing it, I had a second drive which at first I thought had failed. I would have lost 2TB of media.

As it turns out, I got one drive working again and got all the data off the set. But in FlexRAID, all the other drives would have remained usable and I would have lost 500GB instead of 2TB. But then it would have been my fault -- I knew one drive had failed and didn't bother to get a replacement installed right away. For that matter, my controller supports a hot spare but I didn't do that either.

For media storage in particular, FlexRAID looks interesting. Less so for data which is frequently changing.

[stanger89]

Originally Posted by Sam

I guess what I don't like about unRAID or FreeNAS or similar is I don't want to dedicate a box to it -- I'd rather be able to use that horsepower for other tasks too.

Yup, if I didn't already have a "dedicated" server and NAS already, the idea of adding a "NAS" like an unRAID or FreeNAS would not be a big deal, might even be desireable, but when I've already got the server, it just doesn't make sense to replicate that (unnecesary) hardware.

What I like about FlexRAID (in theory -- I haven't used it yet) is I can build parity sets over my media drives, and as I grow capacity just increase the number of drives dynamically. Then the drives can spin down independently until one is needed to access data on that drive. For media storage, I really don't need them all spinning all the time, with real-time RAID-5 striping.

Yup, I kind of like that I can just update the snapshot when I change the data (add a new movie/CD/etc).

For media storage in particular, FlexRAID looks interesting. Less so for data which is frequently changing.

Yeah, I think it could be a good compliment to other forms. For things like Music and Movies, where you manually and intentionally modify the data at discrete and "infrequent" intervals (ie not continuously), and the bandwidth requirements don't necessitate striping, it seems great.

Especially with 1TB drives where the the size of the components means having a single "virtual" volume is not as valuable as with smaller drives.

And then yeah, as we've mentioned, not having all the drives continously spinning would be nice.

[Shield]

Originally Posted by mikejaner

Don't you mean Hardware RAID? If I take my Software RAID 5 array created in Windows Server, and move the disks to another Windows server with completely different hardware, it will see the array.

I think you mean an integrated motherboard based Hardware RAID.

Yes, I meant integrated motherboard type Raid...

[paulbeers]

Originally Posted by myoung84

I notice you have 4 media extenders. Do you have any problems in the rare event you watching 4 separate movies from each extender?

Truthfully, I have never tried it. It is just my wife and I so we never watch more than 2 movies at any one time and even that is rare. I can tell you, I do not think freenas in RAID 5 handles multiple hard drive accesses at one time well. Whenever I try to copy two things to it at one time, it takes considerably more time than just copying one and then the other. After reading about FlexRAID, I am thinking about giving it a try. Too bad I will have to use a 6th hard drive (for OS).