How to set up RAID in El Capitan

I just did it, successfully - quit & restart with Option/Command/R - open Disk Utilities & BINGO! there it is> RAID as in Yosemite - I dragged my 2 HDs into it & I was good to go on a restart - no Terminal No nothing - Apple did't even know about it

Rock on!

Al

Not all machines that can run El Capitan can run OS X Internet Recovery with RAID support as described by @Redcat7. (Apple describes which machines can be upgraded here, and my 2009 Mac Mini isn't on the list.) In this case, the command line option described by @tonyrhap (also described here) is the only way to go. Installing El Capitan on the RAID is also tricky; to do so you'll have to boot to OS X Recovery from a non-RAID drive (if not your primary drive, just hold down the Option key at startup to choose it). Worse still, you can't recover a Time Machine backup to the RAID volume (say, if you want to upgrade your primary drive to a RAID 0); you'll have to do a base install and then use Migration Assistant to do so. Finally, the installer won't install an OS X Recovery partition on your RAID volume, so you'll always have to maintain a backup drive to do recoveries. A PITA for sure, but worth the massive speed improvement IMO.

So for RAID1, would you type:

diskutil appleraid create mirror LaCieRAID1 JHFS+ disk0 disk4

or this:

diskutil createRAID mirror LaCieRAID1 JHFS+ disk1 disk2

It was a little contradictory reading:

https://developer.apple.com/library/mac/documentation/Darwin/Reference/ManPages/ man8/diskutil.8.html

Also, what is JHFS+?

thanks,

Wow! All day talking to Apple and they gave me nothing.. One quick but careful study of this step by step guide & I was able to configure my torched G-Raid 8T drive as a RAID0. Thank you!

How to Create a RAID in Mac OS 10.11

The graphical interface of Mac Disk Utility in Mac OS 10.11 (El Capitan) does not include the ability to create a RAID. However, the Mac Terminal can still create a RAID with simple text commands.

IMPORTANT! Before proceeding, please safely eject and then physically disconnect all external storage devices (external hard drives, SD cards, etc) from your Mac computer, except the device on which you want to create the RAID.

IMPORTANT! Do not attempt the following while your Mac is in Recovery Mode. Proceed only when your computer has started normally.

If you want to create a software RAID in Mac OS 10.11, please follow these instructions:

1. From the Desktop, select Go from the top menu bar, then Utilities > Terminal.
2. Type the following:
   diskutil list
   A list of all storage devices connected to or inside your computer will appear.
   
3. Find and note the external, physical drives that you want to include in the RAID.
   E.g., disk0 and disk4
4. Decide which RAID mode you want - striped (RAID 0) or mirrored (RAID 1).
5. Type the following for RAID 0:
   diskutil appleraid create stripe [Array Name] JHFS+ disk_ disk_
   For example: diskutil appleraid create stripe LaCieRAID0 JHFS+ disk0 disk4
   

I didn't see the RAID support when I booted from the internet recovery. Running current version, iMac (2015).

Hello, I am looking to do this too. I don't see the RAID option, is there something I am missing? Thank you.

No, that is not the solution in this thread. Redcat7 posted an actual solution. Reboot your computer while holding down Option-Command-R. This will load Apple's web-based set of disk tools, which still offers RAID support.

Additional: Don't make the same mistake I did. I used SoftRaid's demo period to create the RAID, thinking that I wouldn't need it after that. Unfortunately (but understandably) SoftRaid uses a proprietary driver that will expire along with the software after 30 days. I would have been willing to purchase the software as I found it to be excellent, but not for $300...

excellent, thanks for the help. yes, that boot up trick worked but it seems each of my drives is already a striped RAID and I'm having issues making them both into a mirrored RAID. Since you've been so helpful already, do you have any suggestions on that front?

What I had to do was go back to the disk tools on my computer and format each of the drives individually (I wasnt able to do this in the web-based tools). Then, reboot (command-option-R) to reload the web tools. Once there, I selected the RAID option I wanted, then dragged the drives into the field. Don't try to drag the volumes; just the formatted drives. To make this a bit less confusing, I named each of the drives RAID 1, RAID 2, etc, when I formatted them.

just a reminder that you will lose all data on the drives when you do this (I'm sure you know this. I'm saying it for other readers).

So I found this on the LaCie site. It shows a simple way to create a RAID in Mac OS 10.11. I don't see why this wouldn't work for any brand of drive though. It worked very well for me.

http://knowledge.lacie.com/articles/en_US/FAQ/007650en?language=en_US&wwwlocale= en-us

Yout are absolutely right; the terminal option has always been available. Those of us who are not terminal savvy were looking for a drag and drop option. After following your link, I still feel that the web-based Disk Tooks solution is orders of magnitude simpler, but kudos to you for mastering what looks like alphabet soup to me.

RAID0? It is good and faster than single disk, but if it crashes, bum deal. Don't recommend it for too long. And do back ups continually.

I do photography and will move to RAID5 as soon as I can. Three back up methods. Backblaze, TM, and CCC.

Ron98GT wrote:

Also, what is JHFS+?

thanks,

That is the disk format: OS X Extended (Journaled). In the old days, the disk format used in the Mac was known as HFS (for Hyerarchical File System), then HFS+ when the extended version (introduced with System 8.1) came to be. Journaling was created later.

diskutil appleraid create mirror LaCieRAID1 JHFS+ disk0 disk4

or this:

diskutil createRAID mirror LaCieRAID1 JHFS+ disk1 disk2

createRAID was a synonym for appleRAID create, but it has been deprecated (will stop working in the future).

So, you should use appleRAID create if you are creating a tool or a script that you might use in the future.