Build a RAID with Disk Utility: Tech Culture
About Video Share (0) Transcript Contact us
Tech Culture: Build a RAID with Disk Utility2:51 /
If you have a Mac and some spare hard drives lying around, you can find out how to build your own either superfast or super-resilient RAID using Disk Utility.
>> Wilson: So you saw Brian Cooley's Insider Secret on building your own Raid Array [assumed spelling] out of an old computer and some spare internal hard drives but you say, hey, I'm too lazy and too cheap to take apart a computer to do all that. Well, I've got an Insider Secret on how you can do nearly the same thing with a Mac and some random external drives. ^M00:00:16 [ Music ] ^M00:00:25 >> Wilson: We've all got some external spare hard drives laying around that your geek friends bought you for Christmas, you can even use spare USB drive sticks, but keep in mind one thing, your Raid Array will only be as large as the smallest drive you have attached to it so if you pair up a 1G USB stick with a 250G hard drive you've just wasted 249 Gigabytes. So, first things first, attach your drives into whatever port you want it doesn't matter it could be Firewire, USB, [inaudible] or any combination Mac OS10 doesn't care. Next, start up Disk Utility, you'll find this in the Utility folder of your applications folder, select the drives on the left side panel and a tab labeled Raid will appear in the main panel, select that. Here you can configure a Raid Array, give it a catchy name then select the file system type, Mac OS Extended Journal is just fine. There are several kinds of Raids but Mac OS10 offers 3 choices, a mirrored array automatically backs up one drive to another bit for bit, they're no speedier than [inaudible] and you lose half your storage but you can be sure that your data's safe. The second kind is striped; striped arrays take half the data and put it on one drive and the other half the data and put it on the other drive at the same time. It has much faster read and write performance than a single hard drive but if one drive fails you, you lose all your data. Finally, the [inaudible] Disk Set option is available if you want to combine a mirrored array with a striped array for faster drive speeds and backed up data at the same time. So drag both your disks or any number of disks from the left panel over into the Raid Section, be sure to drag the disk and not the partition, which is right underneath the disk. Under Options you can select Raid Block Size, if you deal with a bunch of big files then go with a larger block size, if you've got a database or a bunch of Word documents small block sizes are totally fine, they'll get faster seat times but slower speed. Finally, I like to leave the automatically built Raid Mirror Sets option on, occasionally power will fluctuate on a single drive and cause it not to perfectly mirror the data. In this case, Disk Utility will automatically rebuild the drive for you, hit Create and you're ready to go. A couple of notes, this is a software based Raid, meaning it will suck up CPU cycles as it puts together the data for you but I told it was cheap. Second of all, as cool as Disk Utility is it will not tell you when a disk has failed on a Raid Array so check periodically if a drive has killed itself. I'm Wilson Tang and this has been an Insider Secret. ^M00:02:46 [ Music ]