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6

The Apple provided Disk Utility (and diskutil shell command) will allow you full RAID control over internal and external drives. You do have to erase the drives to add the RAID capability, but then you can join those drives into RAID. That is the only potential drawback to implementing RAID storage on the Mac. Drive spanning, JBOD, striping and mirroring ...


5

The previous answer I gave here was wrong (as is bmike's answer). The previous answer I gave was that if you have this as a problem, a workaround is to create an encrypted disk image that covers the entire AppleRaid set. This works, in theory, but is so horribly slow (like more than 10x as slow as the raw disk access) that it is basically unusable, which ...


4

Yes, RAID 0 is faster than using the drives independently of each other. Whether or not its noticeably faster depends on what kind of application you're looking at. Some setups benefit hugely from a RAID 0 setup, while for others, its pretty marginal. There's also the convenience of everything being treated like one big drive. I will however say that ...


4

I was unable to find how to rebuild the RAID from disk utility after a couple of hours of research. However, I managed to do it from the command line. sudo diskutil list // to get a list of disks. Note the disk number of your new disk (e.g. disk4) sudo diskutil appleraid list // note the uuid of the raid in question sudo diskutil appleraid add member disk4 ...


3

Disk Utility will only support RAID 1 and 0 using software raid. If you have the RAID Card for the Mac Pro, you can configure RAID 5. I've never actually used or configured one of these in the wild so I can't give you exact specifics on using it.


3

My guess would be that Apple prefers to have one drive handle only write processes as a backup and read/write from whichever one it considers the main drive. As to why this is, I have absolutely no clue. Seems kind of like a big oversight on their part. I've always kind of gotten the feeling that software RAID is pretty low on Apple's priority list.


3

In the end I went with the most expensive but also the fastest option: #1 which was the Mercury Accelsior PCIe based SSD hardware RAID array (RAID 0 by default which I will keep) in a Mercury Helios Thunderbolt PCIe chassis. The main reason was because it was the only one that mentioned it was bootable (and made a big deal out of that fact). I paid $799 ...


3

In a RAID 0 set established by Disk Utility you, of course, have zero redundancy. The moment one of the drives is lost from the set the entire set becomes useless and you have a volume failure. If (and only if) no attempt was made by anything to write to the volume while the physical drive wasn't there you might be lucky and it will be OK but otherwise you ...


3

Do you have the following files? /System/Libraries/Extensions/HighPointIOP.kext /System/Libraries/Extensions/HighPointRR.kext If so, copy both of them to your desktop, then: Open those kexts and edit the Info.plist. Change all the 'External' references to 'Internal' Copy the modified kexts back to '/System/Libraries/Extensions/' from your desktop. ...


3

You do know that RAID 0 is only striping and not only provides no redundancy, but increases the risk of data loss as the failure of any single drive can mean the loss of the entire storage pool? RAID 0 is only for increasing read and write speeds, for example for video editing. You need at least RAID 1 or 5 for redundancy. That being said, if you're losing ...


2

Yes, it's call RAID 10. With 4 drives you can also do a RAID 5 which is more distributed than a RAID 10.


2

That's basically the only way unless you have one of the older mac pro's with the raid card. if I was you over usb id leave them as stand alone drives.


2

You're thinking of RAID-1 in the wrong way. RAID-1 is not an architecture intended to happily use a single surviving drive within a raid-1 group, and work out mirroring content later. Ultimately it will do that, but that is considered a recovery operation from a failed state, and it will destructively overwrite the mirror drive after replacement. In RAID-1, ...


2

Yes - Apple's software RAID works so that once all the drives are present (or in the case of RAID mirroring - enough drives to ensure one copy of the data is present), you can then mount the RAID volume. Unless you used a third party RAID driver in software or hardware, just getting the drives mounted should work.


2

This can be done from the Disk Utility app or from the diskutil command line. Be warned that you should definitely make a backup before doing anything. I had an issue where the diskutil appleraid enable mirror disk1s2 command I ran wrapped the volume in a RAID set but the partition is now called Apple_RAID_Offline and no longer accessible. Ironically ...


2

For redundancy and performance Apple steers you towards RAID 10. I built a 4 disk array by doing a mirrored pair of striped disks which I then converted to a core storage volume to facilitate easier expansion later and FileVault. I can watch data be written to both stripes with iostat but when I read, presumably this is abstracted by cs, as I see zero bytes ...


2

First let's clarify one thing: RAID is not the same as backup. Building a RAID array out of several (presumably USB) external drives would have many drawbacks. See this question I asked a while back for the explanation. I suspect what you really want is passive and seamless disk/data backup in which case OS X's built-in Time Machine works great. And if you ...


2

Both use the same data structure to create a volume within a volume. One creates a wrapper and the data that is on the disk is scrambled / mapped through a cryptographic function so that the same data written to two different blocks ends up physically different on the drive. That's FileVault 2. The other creates a wrapper and the data on the disk is either ...


2

I think you should be fine. I upgraded to Lion on a Mac Pro that has a RAID 0. While the OS is installed to an SSD, not RAID, Lion still detected the RAID just fine. That's obviously a different scenario than what you have, but as the software RAID is handled at a higher level than the OS, I think you should be fine. Obviously, have a backup ready to go ...


2

Firstly, RAID shouldn't include your backups. Something catastrophic hitting one, will hit the other. Eg. fire, burglary, etc. Ideally, you want to keep one set off site. Using the 2 disks you can keep one at a friends, and sync the up periodically. There are tools that allow you to do this. Alternatively, something like BackBlaze, Amazon Glacier, will give ...


2

Enabling a RAID is destructive to the existing data using disk utility and native OS X tools. You will need to have a temporary copy of the data to re-load it onto the new RAID volume. I know several people that always set up their externals to be in a RAID so they can always mirror up existing drives after the fact to duplicate, snapshot or extend/stripe ...


2

You could setup a Mac OS X Server and boot from the network, however you will need to have a third Mac, which might be costly unless you have an old one. You can purchase the Server from the AppStore for $20. However, booting your Mac from your server requires a moderate internet connection as well as a quick bandwidth (at the place where the server is and ...


2

You're using Apple's RAID which means you need a device which just hosts the discs and then your new laptop will see them and use the existing RAID structure. This rules out NAS. AS these are existing RAID arrays you can't simple merge them together to create a single new RAID. At least, you can't while keeping the data on them. Essentially, in one device ...


2

I have a similar environment here. I would split the task into 2 distinct parts. For changing content, excluding all sample libraries etc. set up a Time Machine; internal, networked, AirPort Time Capsule or NAS-type. To keep any depth of history you will need a lot more space on the Time Machine than you have on the used drives. Copy the static content ...


1

I am a programmer. I create websites and perform analysis on large sets of data. I have also advised clients on setting up their own servers and designed backup systems for them. I assume that these computers and data represent you business and/or your passionate hobby. In either case, I assume that loss of data would be devastating. Based on you brief ...


1

Sorry, no. I am not aware of any utility, Mac, PC, Linux, whatever that will allow you to convert a RAID volume to another type while adding more disks to the mix. Your only option is to back up your data, and set up the RAID that you need to, which will wipe the drives. BTW not sure if Apple supports RAID-10 out of the box, perhaps someone else who knows ...


1

Well you already have a pretty optimal setup. Having the two disks in RAID-0 as your boot drive gives you the greatest possible performance. Just be sure to keep a good backup, since if either disk fails you lose the whole array. Superduper! is great since it makes a bootable backup for you, unlike Time Machine. I highly recommend it. Otherwise you're good ...


1

Unfortunately you have to format everything first. Easiest way will be to use Superduper! or similar software to make an image of your current setup on another disk, then create the RAID array and restore the image back.


1

A mirrored RAID would operate only as fast as the slowest drive in the setup. In this case, unless you are using thunderbolt I imagine the performance would be awful. Another reason not to do a mirror with an external drive (if Disk Utility would even let you) is it'd be too easy have the mirror fail for a number of reasons. I would use Time Machine to ...


1

In this situation, I recommend using disk utility to partition the larger drive such that one partition matches the size of the smaller drive. Then setup the partitions of the same size as a RAID1. You will end up with a mirrored partition of 1.5TB and another un-mirrored partition of 0.5TB based on your first example. Same thing will work for a 2TB + 3TB ...



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