2tb storage/backup setup

[dino213aa]

Putting 4x500 GB drives together just makes up 2TB of storage but no backup or redundancy whatsoever.

I think that was made already clear enough, about the redundancy thing. Mirroring and such doesn't count as "backups" though.

A RAID 10 (sometimes called 1+0) array will give you more redundancy, performance and be able to sustain multiple simultaneous drive failures as opposed to RAID 5.

Like he said before, speed is largely irrelevant for this setup. RAID 6 would also be a better pick than 10 here.

It's more expensive as you'll need 8x500 GB drives to get 2TB. RAID 5 on the other hand will need a more expensive controller card for higher performance but fewer drives. RAID 10 is not as demanding on the controller card as RAID 5, it's also a bit easier to setup and rebuild or expand.

RAID 10 being more expensive? For sure! RAID 5 requiring a more expensive controller? Only if you're going the hardware RAID way, which he isn't, so it's NOT the case.

So it's more like

RAID 10: 8x500 GB + cheap controller card = ~300$ more, counting HDs alone

RAID 5: 5x500 GB + cheap controller card

Using 400 GB drives (10x400 instead of 8x500) will make it a bit cheaper (400 is cheaper per/GB than 500).

500's aren't too bad. Considering the extra power more drives will use, you eventually pay the difference (and often more) in electricity (in AC too). More drives also mean a beefier PSU, or dual PSUs, and a larger case and more ventilation overall, and perhaps more controller cards for the extra ports if required (further negating the price advantage). And filling up a large case so quickly with smaller drives means less room to upgrade down the road, without throwing the old drives away (kind of like buying 512MB sticks nowadays, then having to remove them to upgrade to 1GB sticks later...)

There's always a fine line between getting the absolute cheapest $/GB and being stuck with countless small drives (which use power and create heat). 750GB and 1TB drives are too expensive though.

If 1.5TB will do for now, it's likely the best option (just add more cheap drives later)

I would get a Blu-Ray or HD-DVD drive when they arrive or keep one extra HDD to be able to backup the really really important data in case something happens to the RAID array and/or the comp

This is already supposed to be the backup. I'm no big fan of backuping backups. And Blu-Ray / HD DVD burners cost an arm and a leg, and so does the media. External HDs are far cheaper and are faster, and require no 1000$ drive (that nobody has yet) to work. Personally, I keep a cheap external hard drive at my dad's place (a few 100 KMs away) just in case the place burns down or something. One can just reuse and old drive with a total cost of 0$.

Hey, I ended up ordering a 5 bay enclosure, a PCI eSATA controller that handles RAID 5, 5x500gb Seagate Barricuda 7200.10 drives. Once everything gets here we'll see how it goes.

[dino213aa]

Want a real hardware 4 port SATA RAID card? It's not 40$ anymore, it's more like 300$ for the basic ones (options cost more, more ports costs more). Look at Areca or 3Ware if you want such cards. And you won't find any PCI ones, just PCI-X or PCI-e, so you'd also need a new motherboard or something along with it.

The PCI part is the real bummer. All I have left is a standard PCI slot and a single lane PCIe. It's slim pickins on 1x PCIe cards, and I was unable to find a 1x PCIe, true hardware raid, raid 5 card that supports over 2TB. I suspect that doesn't exist. If there's something I'm missing, please someone let me know.

Until then, here's the setup I went with:

5x500gb Seagate Barracuda 7200.10 drives

Silicon Image SiI3124 4-port card

standard no name 5-bay hotswap enclosure.

For what I'm using it for (media storage) it seems to be just fine. I have noticed some slowdown in CPU performance, but nothing drastic.

Here's another question: Is there any harm in turning off the drives/enclosure when I'm not using it? Also, should turning off the drive restore some of the CPU performance?

Thanks everyone for all your help!

dino213aa

[dino213aa]

well, if you really want some good storage and backup, RAID wont do squat for you.

Umm.. I'm using this now and it works great... plus I have fault tolerance. So I guess RAID really is doing squat for me.

[CoffeeFiend]

The PCI part is the real bummer. All I have left is a standard PCI slot and a single lane PCIe. It's slim pickins on 1x PCIe cards, and I was unable to find a 1x PCIe, true hardware raid, raid 5 card that supports over 2TB. I suspect that doesn't exist. If there's something I'm missing, please someone let me know.

Yeah, I know PCI is kinda slow - alright: REAL slow compared to PCIe. But fortunately, it doesn't affect performance all that much in many common scenarios (e.g. streaming audio/video and such for which PCI is already overkill), or the performance would often be limited by something else (like the network).

I'm dreaming of a nice PCIe card too, but when the card costs as much as the drives... As for 1x cards (1 lane), you won't find any as it would be totally pointless: PCI 2.2 @ 66MHz is faster (266 MB/s vs 250 MB/s for a single PCIe lane). That would just be a slower and more expensive card that works in less PCs. AFAIK they're pretty much all 8x (now that's significantly faster than PCI!)

Here's another question: Is there any harm in turning off the drives/enclosure when I'm not using it? Also, should turning off the drive restore some of the CPU performance?

Well, I don't think just killing off power to drives is such a good idea. And it won't change performance. Performance is only affected when you access the array (RAID5 is computationally intensive - XOR'ing everything for parity). Hardware RAID is less CPU intensive, but it comes with a price (like 300$ extra for a 4 port card).

[dino213aa]

Well, I don't think just killing off power to drives is such a good idea. And it won't change performance. Performance is only affected when you access the array (RAID5 is computationally intensive - XOR'ing everything for parity). Hardware RAID is less CPU intensive, but it comes with a price (like 300$ extra for a 4 port card).

I've only been turning the drives off if I turn the CPU off (or if I leave the CPU in an extended sleep mode)... no point in leaving them on if the PC isn't even on, eh?

As cool as I think true hardware raid would be, I think I'm probably doing fine the way I am... just too many hurdles to deal with for not enough benefit.

As for slowdown, you're right.. I think I only notice overall slowdown when I'm accessing the array. Then again, I'm also usually multitasking (resampling, playing audio, writing to another drive, etc.- all at once) which may have something to do with it

Overall, I feel like I came up with a decent solution. May not be perfect or the very best, but I did achieve my basic goals of expanded storage and fault tolerance.

[nmX.Memnoch]

I gotta throw my vote in there for hardware RAID as well...even if it's a hardware/software controller that's basically controlling things through the driver but still using the system CPU. Read on...

All I have left is.....a single lane PCIe. It's slim pickins on 1x PCIe cards, and I was unable to find a 1x PCIe, true hardware raid, raid 5 card that supports over 2TB.

You're right. You won't find a true hardware RAID controller that supports RAID5 in a PCIe x1 card. The lowest those come in is x4 and the price tag is significantly higher. You can however, get yourself some higher throughput than using a PCI card by getting this:

http://www.newegg.com/Product/Product.asp?...N82E16816115029

It's not "cheap" as quasi-hardware RAID controllers go, but it's still better than using the OS features. And what I mean by quasi-hardware is that it doesn't have a dedicated processor on the card for doing the RAID5 XOR operations...it'll still use the system CPU. BUT, it'll make the array more portable (i.e. upgrading your motherboard will be MUCH easier) as well as provide some custom management utilities. Personally, I'm not a big fan of HighPoint products (haven't been since the old Abit BX6-2 days), but you may be able to find another PCIe x1 controller that'll do the same thing. I just found that one on a quick search.

I haven't been purchasing anything but 3ware controllers for the last few years...at least for my PATA/SATA setups. They're easy to configure and offer very good performance.

[dino213aa]

It's not "cheap" as quasi-hardware RAID controllers go, but it's still better than using the OS features. And what I mean by quasi-hardware is that it doesn't have a dedicated processor on the card for doing the RAID5 XOR operations...it'll still use the system CPU. BUT, it'll make the array more portable (i.e. upgrading your motherboard will be MUCH easier)

Hey, thanks for the suggestion. Unfortunately, I don't see where this has an eSATA output, so I'd end up using my last slot for a sata-to-esata bracket... plus, considering it's mainly serving up music files, I'm still left doubting it's really worth it. I mean, I don't doubt that hardware RAID is the way to go, but for what I'm doing, I'm not sure it's really worth it to race out and get a new motherboard and a hardware RAID controller and go through all that work (and time) just to save a few CPU cycles on writes... especially since I'm not doing much "writing" anyways.

Just trying to weigh cost vs benefit and not let my geekiness get in the way of practicality.

Edited February 22, 2007 by dino213aa