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My Harddrives are not showing up.

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Cameron Glegg
My Harddrives are not showing up.
on Oct 27, 2010 at 9:23:04 pm

Hi this is a complicated problem I know but I am looking for some guidance.

I will walk you through what happened.

I am running a Mac Pro 2010 tower and inside I have all 4 HDD slots used. I was using one of these drives for about a month without taking it out of the case. Then I decided to take it with me to the office, something I do quite often with all of my drives.

So I loaded the Drive (and another drive) into my external 2-Bay RAID tower. When I got to my office I plugged the tower in (to an iMac) and turned it on, but I forgot to check what RAID setup I was using. It was in RAID 0 mode so it did not recognize my two separate drives (makes sense) so I switched it to JBOD mode so that I could use them as separate drives (which they are) but it wont boot the image on the drives now.

Since this I have taken them out of the external 2 bay drive and put them both into my Mac Pro tower and they are doing the same thing.

I am thinking maybe when I booted them in RAID 0 Mode the Raid card did something to the drive but I cannot figure out what it was or how to reverse it.

Any help would be amazing, or another forum were my question might be answered would be great too.

Thanks a lot everybody and keep posting!


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Bob Zelin
Re: My Harddrives are not showing up.
on Oct 28, 2010 at 1:06:31 am

So I loaded the Drive (and another drive) into my external 2-Bay RAID tower. When I got to my office I plugged the tower in (to an iMac) and turned it on, but I forgot to check what RAID setup I was using. It was in RAID 0 mode so it did not recognize my two separate drives (makes sense) so I switched it to JBOD mode so that I could use them as separate drives (which they are) but it wont boot the image on the drives now.

REPLY - You have not explained if your 4 drives in your Mac Pro were all raided together RAID 0. If that is the case, the drives must be used all together. You cannot seperate the drives - they work as a group. If you then switched it to "JBOD mode" - just a bunch of drives - you have destroyed the RAID group, and you have lost all your data. If you lose even one drive in a RAID 0 group, you lose ALL of your data. This applies to RAID 3, RAID 5 and RAID 6. With all the wonderful protection, if you seperate out the drives, or use a software utility to "destroy" the RAID 5 group (for example) and turn it into a JBOD (no raid), all your media disappears. End of story. can you recover it ? NO.



Since this I have taken them out of the external 2 bay drive and put them both into my Mac Pro tower and they are doing the same thing.

REPLY - you converted your RAID 0 into a JBOD with software, and now you are trying to just get back to normal, before you moved the drives. Your media is gone. You can't seperate out a RAID group. The drives must travel and attach together. Had you not tried to create a JBOD, your media would have come back once you got it back into your MAC Pro with all 4 drives (you have not described your original RAID configruation, I assume you had a 4 drive RAID). Even if it was a 2 drive RAID 0, the minute you delete the RAID 0, and create a JBOD to have seperate drives, there is no longer any media on your drives.


I am thinking maybe when I booted them in RAID 0 Mode the Raid card did something to the drive but I cannot figure out what it was or how to reverse it.


REPLY - you can't reverse it once you changed the RAID. All RAID controller cards are different. For example, if you create a RAID 5 group in a Dulce Systems RAID 5 array, and then switch these drives into a Cal Digit or a Sonnet RAID 5 drive array, you CANNOT read the data. It is formatted specfically for that RAID host controller. The only thing that can "travel" is a RAID 0 group - and even that depends on the enclosure you are using. For example, a RAID 0 group in a Sonnet chassis can be read by Cal Digit chassis - but only in the older S2VR Cal Digit - the new Cal Digit drive chassis have built in raid controllers, so they won't recognize the RAID 0 group created by the Sonnet.

Is all of this confusing - YOU BET ITS CONFUSING. It is your fault for thinking that you can just pop RAID group drives in and out, and not get into trouble. Even when I have to replace a RAID 5 group from one defective chassis, into an updated chassis from the same manuifacturer - I still sweat to hope that it works.

You have learned a hard lesson.

Bob Zelin



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Cameron Glegg
Re: My Harddrives are not showing up.
on Oct 28, 2010 at 1:38:16 am

Woah! That was kind of harsh.

Let me explain again. These were not Raid 0 Drives. They were just two drives set up on their own. A 1tb and a 2tb. SO my plan was to use the drives in the tower as JBOD, but I accidentally turned the drive on while it was still in Raid 0 mode. I did not set up any drives as Raid and think that I could just throw them around or something. Contrary to what you might think I am not a moron.

I feel like you may be being a little bit harsh. I was not aware of any hardware that would change a disk image arrangement by just turning it on. I did not change anything in Disk utility.

It is a Datatale drive, if that makes any difference. Can anybody help me rather than chastise me for something that I already feel pretty stupid about.

Cameron Glegg
Editor, Colour Corrector, Post Supervisor
Ying-Wah Pictures


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Bob Zelin
Re: My Harddrives are not showing up.
on Oct 28, 2010 at 3:25:15 pm

Let me explain again. These were not Raid 0 Drives. They were just two drives set up on their own. A 1tb and a 2tb. SO my plan was to use the drives in the tower as JBOD, but I accidentally turned the drive on while it was still in Raid 0 mode.

REPLY -
I am not familiar with your enclosure. If your enclosure automatically creates a RAID array (RAID 0), then inserting two drives that are not RAID 0 may create a RAID 0 array, destroying any media on your drives. As you know, if you take two single drives, and stick them in a MAC Pro tower, they appear as two single drives. If you use Apple disk Utility to create a RAID 0 (with the RAID tab), this is a manual process. When you create the RAID 0 stripe group, you lose your data. However, when you said "I accidentally turned on the drive while it was still in RAID 0 mode" - the raid controller that is built into your chassis may be designed to autodetect new drives, and instantly create a RAID 0 group with two new drives in them. I know they are not new - you had your data on them - but the RAID controller did not see the RAID0 group that it created, and may have created a RAID 0 group. Many companies do this to make it easy for users to not have to worry about reading a manual, or figuring out how to setup a raid, so it happens automatically.


I did not set up any drives as Raid and think that I could just throw them around or something. Contrary to what you might think I am not a moron.

REPLY - hey, I am a moron - I do stupid things EVERY DAY - that is called a LEARNING EXPERIENCE.


Bob Zelin



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Jon Schilling
Re: My Harddrives are not showing up.
on Oct 29, 2010 at 6:28:22 pm

Cameron,

I wish I could give my 2 cents on an answer, but I really don't have much for you on your issues, except that you should contact the manufacturer of your hard drive chassis & give them a rundown on everything you did & what happened, hopefully they can help.

For future reference, before you create a RAID set, you don't want to be mixing drives, models and capacities. You should use matched hard drives, same model, same capacity.

I wouldn't even run mixed drives in non-RAID JBOD, (just a bunch of disks).

Good luck!

Jon Schilling
RAIDON-USA Technology
STARDOM Storage by RAIDON
15356 East Valley Blvd., Suite B
City of Industry, CA 91746
Tel: 626-333-7888
http://www.stardom-usa.com



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