6 Replies Latest reply: Oct 17, 2012 11:04 PM by babowa
davidkazuhiro Level 1 (0 points)



I'm trying to set up a RAID1 array with two 2.0 TB HDDs on my iMac.


While setting up the RAID, my computere crashed. I rebooted, and it crashed while starting up saying there was a kernel panic. I turned off the HDD's and startup up without a problem. Once I turned on one of the HDD's though, my computer crashed again.


Here are the steps I took.


  1. Open brand new HDD's from box
  2. Turn on HDD A
  3. Plug in HDD A to USB
  4. Time machine prompts if it can use it for backups, I say no
  5. Repeat steps 2-4 for HDD B
  6. Open Disk Utility
  7. Select HDD A
  8. Click RAID
  9. Drag both HDDs into the list
  10. Click options
  11. Select 256K block size
  12. Check "Automatically rebuild RAID mirror sets"
  13. Click OK
  14. Click Create
  15. Computer crashed
  16. Hold power button down to turn off
  17. Press power button to turn on
  18. Computer crashes while starting up
  19. Hold power button down to turn off
  20. Turn off both HDDs
  21. Press power button to turn on
  22. Computer starts up without a problem
  23. Turn on one of the HDDs
  24. Computer crashes after about 20 seconds


Any idea why this is happening? What should I do?


Computer Specs

iMac (27-inch, Mid 2011)

Mac OS X

Version 10.7.4

2.7 GHz Intel Core i5

15 GB 1333 MHz DDR3


External HDD specs (both are identical)

Model: Buffalo HD-EB2.0TU2J

Interface: USB 2.0

Data Transfer Rate: 480 Mbps

Supported OS: Mac OS 10.4+ (and Windows but that's irrelevant)

iMac, Mac OS X (10.7.4)