I have just installed two new 3Tb drives in my MacPro 4.1 (OSX 10.8.4) and cannot find the RAID option in Disk Utility. I was hoping to set these up as a RAID1 set. RAID is an option for my SSD and for the other 640Gb HDD installed there ...
Mac Pro, OS X Mountain Lion (10.8.4)
The RAID pane appears across the top with First Aid, Erase, Partition, RAID, and Restore AFTER you select a drive by Hardware_name (justified-left in the list in the left pane.
If those new Drives have not appeared by Hardware_name in the left column, they have failed or or not mating properly with the connector at the back of the slot.
If you have the Mac Pro RAID card installed, this is a completely different set of issues.
If that was the case, as it is for my SSD and 640Gb HDD, there would be no problem, but the RAID option does NOT appear for the two new drives. Why?
Are they initialized for use with a different Partition scheme, such as MBR, or set up with existing partitions ??
To protect you, Mac OS X does not want to clobber drives unless they are "Erased" or "Not initialized".
They were both brand-new Seagates and I initialised them with only a single partition and Mac OS Extended format - standard Mac drives. They're both visible and i can validate them in Disk Utility no problem. It's weird. The RAID option does not appear at all when either of these drives is selected.
I click on the raw drive (SEAGATE1234) not the user partition, and the RAID tab is there.
I am not sure you want to ever mirror SSDs.
People do use stripe and people should always have a restore image of any SSD.
Yes you can have failures for which a restore image is first essential item.
Only then consider mirror, of like identical models of drives.
"Green" are not suitable for mirror or stripe, or even for most data storage if you want performance and don't want frequent head-parking and spin down that green drives entail.
I would format each on its own, test each to insure they work and they are identical in tests of IOPS and r/w behavior. Then drag them into the RAID window.
WD goes from 2TB to now 4TB but no 3TB in the Black model series.
I would use this for my data needs, and maybe use Green for backups, and you want something large for TimeMachine.
http://www.amazon.com/Black-Desktop-Hard-Drive-WD4001FAEX/dp/B00A2IM76K/
I don't use 10.8, so I do not know if they have "re-arranged the furniture". Is RAID shown on the ToolBar or any of the Menus?
The Disk Utility app looks the same as it has done for years, and Yes, RAID is available for the 640Gb HDD and the SSD, but not for either of the new 3Tb HDDs. I've installed RAID0 and RAID1 pairs many times before but have never seen the RAID option unavailable.
I said this earlier, worth repeating here:
RAID
OS X supports drive striping (RAID 0) for improved performance, drive mirroring (RAID 1)
for higher reliability, and mirrored striping (RAID 10) for improving both performance
and reliability of storage. In addition, you can reformat storage in the background: You
can promote a single volume to a mirrored volume, split a mirrored array into two
volumes, or rebuild RAID volumes.
OS X Mavericks 10.9
Core Technologies Overview
June 2013Core Technologies Overview 2
http://images.apple.com/osx/preview/docs/OSX_Mavericks_Core_Technology_Overview. pdf
Thankyou. I understand RAID 0 through 5, I am not trying to mirror or stripe an SSD, and I don't really care what WD make, although I do agree that WD's Green drives are a good way to handicap yourself, a trap you will notice I have avoided.
I am simply trying to create a RAID1 set from two brand-new identical Seagate Barracuda 3Tb drives, and for reasons unknown to me, and clearly to you either, the RAID option disappears in Disk Utility when either of these drives is selected. I am unable to locate anything that identifies limitations or exclusions from a RAID set, and can see no reason why Disk Utility specifically deletes the RAID option from the menu.
I don't understand this either.
In cases like this, I would try an SMC reset or a Restart to see if anything changes.
you didn't mention seagate until after I was replying and I guess you have a chip somewhere else too.
I love seeing make, model of drives and given the high number of problems with 3TB drives posted in this forum all the more so.
One person found that their old drive had a jumper on it, rare, and that the 4,1's will not work with SATA 1.0 (news and first such report).
Always something unknown and new to learn from.
These are brand-new SATA3 Barracudas, and even Seagate said they are mystified, although they did think that Apple had released a hardware update for disks, but when I checked for that and downloaded it apparently my machine doesn't need it.
Did you find a solution to this? I am having the exact same problem. 2 brand new drives that I did a secure erase to. They can be verified but I get no raid tab for either drive. I gett the raid tab for other internal drives but not these 2. I'm wondering if it has something to do witht hte fact that I did a secure erase and wrote 1 pass of zeros?
Thanks,
Are you also using 10.8.4? If not please specify what Mac OS X you are using.
Secure erase with write Zeroes is a great idea for any new or repurposed drive. It securely erases the data and is the classic way of encouraging the drive to substitute spares for any Bad Blocks.
It should have no impact on this mysterious inability to create a RAID from drives over 2.2TB.
These are the first reports of this problem I have seen, and I suggest you get "on record" with Applecare by contacting them so they will know this is an issue. If you are a developer, through developer tech support, and otherwise through a genius Bar or national phone support call.
I'm on the phone right now with applecare and they are totally stumped. The drives are showing a logical partition volume after the the zeroing out. The Apple tech seems very confused by what's going on. I option to erase the drive is gone also. I can erase the volume but not the drive itself.
I just installed new drives in my MacPro and cannot find the RAID option in Disk Utility
