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zgall1 · Sep 25, 2007, 04:00 PM

I would like to set up a RAID array in my family's home that would have around 1 TB of storage and would be accessible through our home network. I am concered only with redundancy. How much would it cost to get this set up and how difficult is it? I have not done anything like this before but I'm pretty sure I could learn how to do it quite easily. I was also wondering how easy it would be to be able to access this array through the network (as opposed to physically bringing the computers (all laptops) to the array)?

Thanks.

besson3c · Sep 25, 2007, 04:30 PM

The first thing you ought to decide is whether you want to go with RAID 1 or RAID 5, and whether you want to do it with software or hardware. Have you looked into these issues?

zgall1 · Sep 25, 2007, 05:19 PM

I'm thinking RAID 1 run by software would be sufficient. I'm assuming that would be the cheapest option.

besson3c · Sep 25, 2007, 05:51 PM

I've never priced 2 1 TB drives... You might want to compare this price to, say, several 500 gb drives with a RAID 5 PCI card if you are looking for a nice cheap option. The nice thing about RAID 5 is that you can keep adding to it as your needs grow, and it is less wasteful.

zgall1 · Sep 26, 2007, 01:00 AM

What is the price range for the RAID 5 setup?

besson3c · Sep 26, 2007, 09:19 AM

You can get a RocketRAID card for under $100:

Newegg.com - Buy Computer Parts, PC Components, Laptop Computers, Digital Cameras and more!

And 500 gig drives for $100/each

The trick is finding an enclosure for the drives - be it a standalone one or an unused PC or Mac.

ginoledesma · Sep 26, 2007, 03:37 PM

Depending on your budget, you can get a variety of solutions. I prefer small, stand-alone units as much as possible, but we pay the price for convenience and design. Here's some for your consideration:

1. D-Link DNS-323 (US$180) + 2 x 1TB SATA Drives (US$350/drive) -- The DNS-323 is essentially a small Linux computer that can take 2 SATA drives and use them in either JBOD, RAID-0, or RAID-1 configuration. It's hackable if you're into that. I use one with 2x500GB drives. It's got a GigE port so it works well for me. Avoid the Netgear's similar offerings (the Storage Central) -- they don't work with Macs and are pain-in-the-*** to deal with in Windows.

2. At some Fry's stores, I saw Iomega and Buffalo selling 1TB NAS using some combination of either 4x250GB drives or 4x300GB drives. They were priced in the $380-$500 range. I forget the exact models, but I'd do some research to see what protocols they support (AFP, FTP, SMB).

3. A custom solution is to get a stand-alone USB device and then hook it up to an Airport Extreme base station or similar wireless access point that can share USB mass storage devices.

4. More expensive offerings are the ReadyNAS, made by Infrant (which was bought by Netgear).

zgall1 · Sep 27, 2007, 07:55 PM

Thanks for the help guys. I think I'm going to go with a software controller. What options do I have on the Mac?

Timo · Sep 27, 2007, 08:16 PM

SoftRAID.

besson3c · Sep 27, 2007, 09:30 PM

Originally Posted by Timo

SoftRAID.

You can only do RAID 0 and 1 in OS X via software, AFAIK.

ginoledesma · Sep 28, 2007, 01:03 AM

You could always take advantage of RAID-1 and RAID-0 by implementing it as RAID-10. Much more reliable than RAID-5 in my experience, but you do pay a premium on storage. Otherwise, you could always build a Linux box and use md to implement your choice of RAID-0/1/5/10.

BLAZE_MkIV · Sep 28, 2007, 08:40 AM

FreeNAS: The Free NAS Server - Home

a little searching will find more.

zgall1 · Sep 28, 2007, 05:50 PM

If I buy this enclosure and 4 of these drives, will I be able to set up a RAID 1 using Disk Utility? Also, would it be possible to add to this setup in the future? Lastly, how would the RAID connect to the computer that I'm using as a server (it is not really a server)? Thanks again for all the help

besson3c · 07:14 PM

Originally Posted by BLAZE_MkIV

FreeNAS: The Free NAS Server - Home

a little searching will find more.

FreeNAS looks really good. It was a former SourceForge project of the month...

Just to be clear to those new to RAID, FreeNAS is a server you can install on a separate PC. It runs its own OS - FreeBSD. AFAIK you can not run it concurrently with OS X on a Mac, but of course you can connect to it from OS X or any other machine.

ginoledesma · Sep 29, 2007, 02:55 AM

Originally Posted by zgall1

If I buy this enclosure and 4 of these drives, will I be able to set up a RAID 1 using Disk Utility? Also, would it be possible to add to this setup in the future? Lastly, how would the RAID connect to the computer that I'm using as a server (it is not really a server)? Thanks again for all the help

This enclosure requires a SATA connector, so you'll need a Mac or PC with an external SATA port. The page doesn't explain much, but for its price, I'm guessing it requires the software to do RAID for it, which means the drives will be exported to the host computer as-is (as individual drives). The computer in turn will make the drive(s) available over the network if you want to access it over the network.

zgall1 · Sep 29, 2007, 12:29 PM

Originally Posted by ginoledesma

This enclosure requires a SATA connector, so you'll need a Mac or PC with an external SATA port. The page doesn't explain much, but for its price, I'm guessing it requires the software to do RAID for it, which means the drives will be exported to the host computer as-is (as individual drives). The computer in turn will make the drive(s) available over the network if you want to access it over the network.

Thanks for the reply. Can you explain what this part means "... encloses 4 hard drives with only 3 bay slots"?

BLAZE_MkIV · Sep 30, 2007, 10:30 AM

I probably means that they fit 4 drives on end in 3 5.25 bays (cdrom sized)

UnixMac · Oct 1, 2007, 01:37 PM

I bought two iOmega hardware RAID boxes (two disks each) for 1.5TB x 2 for $2000 or so, and only had to buy an eSATA card to it to connect via SATA.. you can also use firewire without the card.

it's not capable of RAID 5 if you need that.

zgall1 · Oct 3, 2007, 06:44 PM

I have another question regarding a possible setup. It is inelegant but relatively cheap (especially in Canada where prices are inexplicably higher and most of the cheaper electronics companies will not ship here, including Newegg). I would like to get four of these drives and place each drive in one of these enclosures. I would then hook up the four drives to a four-port USB hub and make them into a RAID using Disk Utility. Would this work?

UnixMac · Oct 3, 2007, 11:21 PM

Originally Posted by zgall1

I have another question regarding a possible setup. It is inelegant but relatively cheap (especially in Canada where prices are inexplicably higher and most of the cheaper electronics companies will not ship here, including Newegg). I would like to get four of these drives and place each drive in one of these enclosures. I would then hook up the four drives to a four-port USB hub and make them into a RAID using Disk Utility. Would this work?

The only problem with this method is that using disc utility to do RAID, is basically software RAID is slower and less reliable than hardware RAID and also take away resources from your CPU and data bus.. I would consider an external RAID box or a hardware RAID card and the internal RAID disks.

besson3c · Oct 3, 2007, 11:50 PM

Originally Posted by UnixMac

The only problem with this method is that using disc utility to do RAID, is basically software RAID is slower and less reliable than hardware RAID and also take away resources from your CPU and data bus.. I would consider an external RAID box or a hardware RAID card and the internal RAID disks.

It isn't using the Disk Utility app, it is doing it at the kernel level. The resources needed for software RAID are quite minimal, and may be negligible for his setup, depending on what he does.

UnixMac · Oct 4, 2007, 12:57 AM

Originally Posted by besson3c

It isn't using the Disk Utility app, it is doing it at the kernel level. The resources needed for software RAID are quite minimal, and may be negligible for his setup, depending on what he does.

I know Disk Utility only does the setup of the RAID and it's not the operation, but I was told by a few sources that software RAID isn't as efficient or reliable, which I'm just passing on.

besson3c · Oct 4, 2007, 01:08 AM

Originally Posted by UnixMac

I know Disk Utility only does the setup of the RAID and it's not the operation, but I was told by a few sources that software RAID isn't as efficient or reliable, which I'm just passing on.

There is a slight difference in efficiency, but I'd really like to put the FUD about reliability to rest.

Software RAID is being used in all sorts of places. It is a viable RAID solution, and is a standard part of Unix distros (including OS X) for a reason - it works just fine. A few months ago people were oohing and ahhing over ZFS, which also includes some software RAID type features. I've been running a production server that has been doing software RAID 1 on FreeBSD for years without a single problem. Besides, there is no guarantee that a hardware RAID card will be any more reliable.

The main reason to choose a hardware RAID card over software is if you need a RAID configuration your kernel doesn't support (or is only experimental), or if you need every last ounce of performance out of your machine. Even then, there are all sorts of things that cause extra I/O and CPU. HFS+ in and of itself is inefficient in terms of I/O. There are lots of variables to account for that also play into performance. On a workstation machine where there is a lot of stuff going on and a lot of things vying for resources at any given time, I'd have *no* problems recommending a software RAID solution. The difference in performance is barely noticeable, if at all - easily covered up by Finder farts

Maybe there was cause for concern with software RAID in years past, but in modern computing software RAID is a totally safe and legit RAID scheme (unless you are doing RAID 0, which I think is fundamentally a flawed RAID scheme). Would pretty much every Unix vendor under the sun include software RAID support in their kernels if there was this level of concern for this?

UnixMac · Oct 4, 2007, 01:13 AM

Good info, thanks for educating and sharing.. I could have saved a few bucks if I had known this!

Timo · Oct 4, 2007, 01:13 AM

^ gotta concur with besson3c, hardware RAIDs are not perfect and I've had one go south on me a couple of times.

At least with a software RAID you have something you can troubleshoot.

besson3c · Oct 4, 2007, 01:20 AM

No problem...

There was an interesting Slashdot article a while ago asking whether big expensive SAN/RAID setups costing tens of thousands of dollars can be replaced with ZFS and commodity disks.

The consensus seemed to be that this is now a viable thing to do if you are on a budget. The big reason to not do this is because the disks that you could buy for a SAN or RAID would generally be of a higher class and grade than bargain basement disks you can get on NewEgg, so the media itself would be less reliable. However, with a RAID 5 setup, you could include a bunch of spare disks which would kick into action when a disk dies. While you would have more disk failures, the redundancy would save you.

The same can be said for servers... In many environments (Google being a good example) they are moving away from big expensive mainframes running something like HP-UX or Solaris and moving to much less expensive Linux clusters. Individually, these machines may not hold their own against the expensive mainframes, but you are covered by being able to afford more nodes within your clusters/pools, and in the redundancy of having all of these nodes (which also often run virtual machines via VMWare or Xen on these servers). There may be a downside in space and power requirements, but the price difference is so great this is becoming an attractive option to many.

Besides, big clusters of brainless drone computers are kind of cool