Four hard drives. One problem.

September 12, 2007 9:40 AM

What can I do with 4 big IDE drives?

I have four biggish IDE drives (is that what they're called?).

I had planned to buy a Firewire 4-bay enclosure and make a RAID out of them, but 4-bay enclosures are spendy and noisy.

I keep seeing deals on 1-bay enclosures ($22 on DealMac! Yeah!); if I pick up four of thoise is there some way I can turn them all into one big drive? Specifically what I want to do is store all my movies and MP3s on one huge server that I can access throughout my house.

Or is there some other way I can use them?

posted by ImJustRick to computers & internet (15 comments total)

My understanding is that RAID drives must all be the same size...someone will come along to correct that if not.

Also, 1 bay enclosures can be had for a lot less than $22.

I would stay away from four single enclosures though, one big bay is probably going to provide better ventilation.
posted by stupidsexyFlanders at 9:53 AM on September 12, 2007

Why combine them? It adds unneeded complexity and another layer of failure to your system. Especially for drives running in hot little enclosures over a slow USB interface anyway. If you must go this route here's a previous ask about this.

I'm no fan of software raid. What I'd do is decide how much storage I need and see if I can get away with using two of the drives as drives and the other two as my hot backups. You can backup easily with the windows backup utility or a simple xcopy command.
posted by damn dirty ape at 10:42 AM on September 12, 2007

If they ever stop working, open then up and pry out the really strong rare earth magnets within. Handle them with care, though.
posted by jquinby at 10:54 AM on September 12, 2007

It sounds like you are looking for logical volume management. I've used LVM on Linux to combine multiple hard drives into one massive home directory, and it worked well.
posted by cmonkey at 11:10 AM on September 12, 2007

From your mention of Firewire and DealMac I'm going to assume you're a Macintosh user. You don't mention the platform, and that's important information when asking a question about what you can and can't do, and how.

" is there some way I can turn them all into one big drive?"

Yes. Look in the help for Disk Utility. It will educate you about how to make a RAID set. It's not difficult and works well. Non-Server versions of OSX won't have RAID-5 support built in, but you have some other potentially useful choices there.

"drives running in hot little enclosures over a slow USB interface anyway."

ImJustRick said "firewire." Firewire isn't as horribly slow as USB.

"I'm no fan of software raid. [...blah blah Windows stuff...]"

Windows software RAID is really, really, really bad. Windows is terrible at volume management in general, but the software RAID is especially terrible. Don't generalize that to all platforms, for which software RAID can often be the best choice. Solaris' ZFS raidz, Linux diskmapper, and even OSX software RAID-1 are all a lot more flexible and reliable than bare drives, and easier to manage than popping into some cornball BIOS utility to manage hardware RAID containers.
posted by majick at 11:25 AM on September 12, 2007

You can RAID drives that are different sizes, however, you are limited to the size of the smallest drives (ie. your array will treat them all as 200GB if you have a 200, 250, 400 and 500).
posted by i_am_a_Jedi at 11:41 AM on September 12, 2007

Drobo?
posted by sharkfu at 11:53 AM on September 12, 2007

sharkfu: The Drobo is SATA only.

You could find a cheap mobo that supports JBOD (Just a bunch of disks), and build a server out of that.
posted by mphuie at 12:23 PM on September 12, 2007

Mounting them internally is a good idea. Many OSes don't like creating soft-RAID on removable devices.

I've been looking at Sun's ZFS for my own RAID needs, though I haven't moved in that direction yet. The trouble is that I don't want to admin another entire OS just for file storage.
posted by Myself at 2:22 PM on September 12, 2007 [1 favorite]

My understanding is that RAID drives must all be the same size

1. All partitions, not physical disks must be the same size, in a software RAID.
2. Windows Home Server has the ability to add removable drives to the local RAID in real time.
3. RAID 5 has automatic redundancy, and with four drives (partitions, really), only about 25% disk overhead.
4. Server 2003 can probably be tweaked to use external drives for RAID volumes. You must first make the partitions Dynamic Disk Volumes, and then join them together with the Disk Management MMC Snap in.
5. But this is all Windows, and you may be looking for Mac-only solutions. Can't help you there.
posted by SlyBevel at 3:50 PM on September 12, 2007

Windows software RAID is really, really, really bad.

Respectfully, this is a load of crap. Windows Server 2003 and Windows Home Server (which is Server 2K3 at core) both manage software RAIDs extremely well.

I've run both hardware RAIDs and Server 2k3 RAIDs. The main differences between hardware and software RAIDs are array speed and ease of use.

Increases in processing power have made it such that most S2K3 RAIDs will be just as fast as a hardware RAID, and in some scenarios, they're faster.

Software RAIDs are far easier to use, as they can be set up, tweaked, and restored from a GUI, whereas hardware RAIDs (such as a RAID-on-card setup) are almost exclusively command line affairs.
posted by SlyBevel at 3:59 PM on September 12, 2007

What you want to do with your 4 drives is create a raid-5 array. This way, if a single drive fails, your data is still recoverable. Even if you have backups of all the data (you should, even on a redundant drive), it will save a lot of time restoring (think about 10,000 mp3s, or whatever). If you aren't going redundant raid, just use 4 separate drives as damn dirty ape says.

Windows software raid works just fine. You can also hack XP to allow raid-5.
A good previous windows software raid thread.

In fact, software raid has some serious advantages, especially for not-so-techy people. With hardware raid, a failed controller card will require an identical replacement card, but you can just put your software raid drives in any system with the right operating system.
posted by Chuckles at 11:00 PM on September 12, 2007

Hardware RAID is for the people that can buy one controller to run it and 10 spares for later. Or very, very lucky people.

A quick look at the previous windows software raid thread shows that a stupid dependency on the system disc prevented the migration of the _undamaged_ raid. And the thread ends with no solution found. So yeah, without going into my indepth opinion over windows "raid", i can tell you that few times is the bad choice so clearly highlighted.
posted by CautionToTheWind at 8:09 AM on September 13, 2007

Ya.. I'm pretty sure that error message mentioned in the other thread is just typical of Windows being overly alarming, and that there is no stupid dependency. I expect you just have to say go ahead, and everything will work out fine. On the other hand, you never know :P
posted by Chuckles at 10:59 AM on September 13, 2007

Sorry for not being clear... I tagged the question OS X but should have been a little more explicit I suppose.

Thanks for the answers so far.

Yes. Look in the help for Disk Utility. It will educate you about how to make a RAID set. It's not difficult and works well. Non-Server versions of OSX won't have RAID-5 support built in, but you have some other potentially useful choices there.

Excellent.
posted by ImJustRick at 3:54 PM on September 13, 2007