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HoosPhotog

macrumors member
Original poster
Aug 4, 2011
36
0
I just got two new 3TB seagate drives for my Mac Pro at work (4,1- Snow Leopard) that disk utility will not format. My steps:

-Installed in drive bays 3 and 4
-reboot, get message that computer can't read drive, click initialize to open disk utility
-choose erase tab, Mac OS Extended (Journaled), name and click Erase
-confirm in pop-up (which notes that disk is unformatted)
-Almost immediately get error pop up: "Disk Erase failed with the error: Could not unmount disk"

I should note I get the same error trying to partition rather than erase (for 1 partition, Mac OS Extended (Journaled), set to GUID partition map)

Any ideas? I am assuming that Snow Leopard does support 3TB drives, right? And that disk utility can format them (without 2.2TB limit)? Thanks!
 

Loa

macrumors 68000
May 5, 2003
1,723
75
Québec
Hello,

I wanted to confirm that 10.6 can format 3TB: I've done it many times.

Have you / can you try it in an external enclosure? It shouldn't matter, but then again, DU should be able to format them...

Loa
 

wonderspark

macrumors 68040
Feb 4, 2010
3,048
102
Oregon
I have a Hitachi 4TB in slot 4 of my Mac Pro, so it's not related to disk size.

----------

The drive is one 4TB volume, and I'm on 10.6.8.
 

flatfoot

macrumors 65816
Aug 11, 2009
1,010
3
I just got two new 3TB seagate drives for my Mac Pro at work (4,1- Snow Leopard) that disk utility will not format. My steps:

-Installed in drive bays 3 and 4
-reboot, get message that computer can't read drive, click initialize to open disk utility
-choose erase tab, Mac OS Extended (Journaled), name and click Erase
-confirm in pop-up (which notes that disk is unformatted)
-Almost immediately get error pop up: "Disk Erase failed with the error: Could not unmount disk"

I should note I get the same error trying to partition rather than erase (for 1 partition, Mac OS Extended (Journaled), set to GUID partition map)

Any ideas? I am assuming that Snow Leopard does support 3TB drives, right? And that disk utility can format them (without 2.2TB limit)? Thanks!

Before going to the "Erase" tab, make sure you select the correct drive in the left-hand list.
 

HoosPhotog

macrumors member
Original poster
Aug 4, 2011
36
0
Thanks for the replies thus far. I tried connecting one of the bare drives with a USB - SATA adaptor with no luck, though I think it my have been defective. Attempting to connect the same drive with the same adaptor to a Windows 7 box didn't work either, reporting the USB device was not recognized.

I have one of my IT guys at work trying to slide two of the drives into a G-RAID enclosure- hoping maybe that because it is a newer one, with the quad interface, that the chipset in the drive enclosure will support 3TB drives.

I obviously tried all of the obvious things first (and triple checked that I was selecting the correct drive- obviously didn't want to format one of my in-use drives)

Any other ideas? Anybody know of any issues with seagate drives? I'm starting to think I may have defective drives, but they do spin up when plugged in, and disk utility shows the correct drive ID
 

MovieCutter

macrumors 68040
May 3, 2005
3,342
2
Washington, DC
Thanks for the replies thus far. I tried connecting one of the bare drives with a USB - SATA adaptor with no luck, though I think it my have been defective. Attempting to connect the same drive with the same adaptor to a Windows 7 box didn't work either, reporting the USB device was not recognized.

I have one of my IT guys at work trying to slide two of the drives into a G-RAID enclosure- hoping maybe that because it is a newer one, with the quad interface, that the chipset in the drive enclosure will support 3TB drives.

I obviously tried all of the obvious things first (and triple checked that I was selecting the correct drive- obviously didn't want to format one of my in-use drives)

Any other ideas? Anybody know of any issues with seagate drives? I'm starting to think I may have defective drives, but they do spin up when plugged in, and disk utility shows the correct drive ID

I had this problem with some 3 TB drives in a 3rd party enclosure. For some reason, the Mac saw all 3TB when I used a newer USB 3.0 dock, but wouldn't recognize the full 3TB in the FW enclosure. Once I formatted them in the dock, the Mac saw all of it just fine. No clue what causes this.
 

ActionableMango

macrumors G3
Sep 21, 2010
9,612
6,907
3TB drives are no problem in my experience. Do you have any third party file system drivers or software?

I'd try booting from the install DVD and using Disk Utility to initialize the drives from there. That would rule out any software or settings you've changed on your OS.
 

HoosPhotog

macrumors member
Original poster
Aug 4, 2011
36
0
I don't have any third party file system drivers or software, so I don't think the OS is the culprit.

I did discover an interesting wrinkle in the whole issue today by trying to connect the drives to a Seagate Goflex desktop adaptor (USB 3 version) I use at home with a 3TB external. By connecting this way, I was able to get disk utility to recognize and partition the drives into full 3TB partitions with Mac OS Extended journaled and GUID partition maps. Still connected through the dock, I checked that the drives could read/write, etc. and they checked out.

The problem reappeared when I tried putting the drives back into the bays in the Mac Pro, as they show up there as un-formatted, with a 375GB MS-DOS partition that would not mount, but that could be reformatted. Strange.

I figure there is something in the way Seagate handled the memory block addressing that isn't playing right with the way the Pro Mobo handles SATA-connected devices. Im guessing something in the chipset of the Goflex adaptor mitigates this issue.

Has anyone else had issues like this with 3TB Seagate Barrracuda drives in a Mac Pro? If I can't find some miracle fix, the drives are getting exchanged for Western Digitals, or maybe I'll just stick with 2TB drives.
 

alphaod

macrumors Core
Feb 9, 2008
22,183
1,245
NYC
I have used many different brands (including the Seagate Barracuda) and sizes (including 3TB) in my Mac Pro, none of the drives have issues formatting with Disk Utility. This is on both Snow Leopard and now Lion: No issues.
 

gkddan

macrumors newbie
May 18, 2012
2
0
i also have this issue.

There is an interesting article on a western digital website that basically talks about the difficulty with accessing drives bigger than 2.2TB. http://www.wdc.com/wdproducts/library/WhitePapers/ENG/2579-771501.pdf


The only way i have ever accessed a 3TB drive on a mac is when it is an external drive in a plastic case where it has the usb - sata board inside it which takes care of it or with a modern good quality external enclosure.

with my PC it was a matter of updating my BIOS.

It is a bios related issue that causes the problem. the circuit board in an external enclosure or a sealed external HDD fixes the issue.
 

ActionableMango

macrumors G3
Sep 21, 2010
9,612
6,907
Perhaps only the 5,1 supports 3TB? I have a 5,1 and the OP has a 4,1. What about the rest of you who reported it works?
 

macaroniguy

macrumors newbie
Jul 4, 2012
4
0
I'm having the exact same problem with two Seagate 3TB hard drives in a MacPro.

1) Can't Partition using Disk Utility OR Drive Genius

2) Can't format using Disk Utility OR Drive Genius

My first Mac was a IIx with a 120 meg Rodime hard drive. I think I know what I'm doing. I strongly suspect it's a conflict between OS X and Seagate.

I had a somewhat different problem years ago, that was resolved by "zeroing out" the hard drive. I'm trying that now. Takes something like 7 hours.....

If that doesn't work, both drives go back. In the past, when I bought Seagate drives, even when they were advertised as "internal, bare" they came with a little booklet showing pinouts and jumper settings, etc. Of course those were IDE and this is SATA, still I just suspect there may be a lot of bad ones out there that are getting resold.

Anyway, I haven't found a solution on line yet!

Please, please, if anybody has resolved this, please post!
 

-hh

macrumors 68030
Jul 17, 2001
2,550
336
NJ Highlands, Earth
I'm having the exact same problem with two Seagate 3TB hard drives in a MacPro...

My first Mac was a IIx with a 120 meg Rodime hard drive. I think I know what I'm doing. I strongly suspect it's a conflict between OS X and Seagate.

I've not heard of specific issues with 'bare' 3TB Seagates, but I'd recently picked up a pair of Seagate 3TB GoFlex (USB3) externals and had a good deal of trouble with getting them to behave.

My main problem was that the externals wouldn't "re-wake-up" after the system went to sleep and the drives spun down. In searching around on the web, there's lots of reports of people having had problems for several months now, and it appears quite obvious that Seagate has had an utter mess on their hands with getting their drivers to correctly support Lion.

What finally fixed my 'wake from sleep problem' with the Seagate GoFlex externals was to install the absolutely latest drivers from Seagate's website.

Fortunately, I hadn't yet run Segate's installer that came on the HDD, which is probably worth mentioning for future readers who find this post... I had assumed that for something as mundane as an external HDD that it would be plug-n-play, with no special driver install required before its use.


-hh
 

monokakata

macrumors 68020
May 8, 2008
2,035
582
Ithaca, NY
I've mounted and initialized and partitioned 3 of the Seagate 3 TB bare drives.

Two of them in a Mac Pro 1,1 (Lion) -- no problems at all.

One of them in a Mac Pro 5,1 (Lion) -- no problem there either.

I don't know what's causing your problem, if it's not something to do with SL, but if your MP is functioning properly, the drive should behave itself.

Have you switched drive bays, just in case the one you're using is wonky?
 

clemesha

macrumors newbie
Sep 3, 2010
1
0
I'm having the exact same problem with two Seagate 3TB hard drives in a MacPro.

1) Can't Partition using Disk Utility OR Drive Genius

2) Can't format using Disk Utility OR Drive Genius

My first Mac was a IIx with a 120 meg Rodime hard drive. I think I know what I'm doing. I strongly suspect it's a conflict between OS X and Seagate.

I had a somewhat different problem years ago, that was resolved by "zeroing out" the hard drive. I'm trying that now. Takes something like 7 hours.....

If that doesn't work, both drives go back. In the past, when I bought Seagate drives, even when they were advertised as "internal, bare" they came with a little booklet showing pinouts and jumper settings, etc. Of course those were IDE and this is SATA, still I just suspect there may be a lot of bad ones out there that are getting resold.

Anyway, I haven't found a solution on line yet!

Please, please, if anybody has resolved this, please post!

I Too Have had problems mac OS 10.7 and segate 3TB drive. So Far I have been able to track it down to the Oxford Chip Set. I Have been trying to use the Segate in a external OWC case with it showing as only 800GB. As other people I tried all different formats exFAT, NTFS etc but still showed as only 801GB. Under bootcamp Windows 8, I could reformat it as its full 3TB but, reboot into Mac OS and it was back to the 800GB. So I thought it might be the chip set in the controler of the external case. There for I used an other external case with a different chip set and low and behold it now shows up as 3TB. On further net searching I saw some reference to Segate and the Oxford chip set as having problems. A quick search found that the OWC case used the Oxford chip set. So here is the support for my conclusion jump that it is the Oxford chip set.

----------

I'm having the exact same problem with two Seagate 3TB hard drives in a MacPro.

1) Can't Partition using Disk Utility OR Drive Genius

2) Can't format using Disk Utility OR Drive Genius

My first Mac was a IIx with a 120 meg Rodime hard drive. I think I know what I'm doing. I strongly suspect it's a conflict between OS X and Seagate.

I had a somewhat different problem years ago, that was resolved by "zeroing out" the hard drive. I'm trying that now. Takes something like 7 hours.....

If that doesn't work, both drives go back. In the past, when I bought Seagate drives, even when they were advertised as "internal, bare" they came with a little booklet showing pinouts and jumper settings, etc. Of course those were IDE and this is SATA, still I just suspect there may be a lot of bad ones out there that are getting resold.

Anyway, I haven't found a solution on line yet!

Please, please, if anybody has resolved this, please post!

I Too Have had problems mac OS 10.7 and segate 3TB drive. So Far I have been able to track it down to the Oxford Chip Set. I Have been trying to use the Segate in a external OWC case with it showing as only 800GB. As other people I tried all different formats exFAT, NTFS etc but still showed as only 801GB. Under bootcamp Windows 8, I could reformat it as its full 3TB but, reboot into Mac OS and it was back to the 800GB. So I thought it might be the chip set in the controler of the external case. There for I used an other external case with a different chip set and low and behold it now shows up as 3TB. On further net searching I saw some reference to Segate and the Oxford chip set as having problems. A quick search found that the OWC case used the Oxford chip set. So here is the support for my conclusion jump that it is the Oxford chip set.
Best Wishes
Peter
 

meteorman69

macrumors newbie
Jan 28, 2009
2
0
Cleveland, OH
Seeing only 2.2TB of 3TB Seagate ST Drives

i also have this issue.

There is an interesting article on a western digital website that basically talks about the difficulty with accessing drives bigger than 2.2TB. http://www.wdc.com/wdproducts/library/WhitePapers/ENG/2579-771501.pdf


The only way i have ever accessed a 3TB drive on a mac is when it is an external drive in a plastic case where it has the usb - sata board inside it which takes care of it or with a modern good quality external enclosure.

with my PC it was a matter of updating my BIOS.

It is a bios related issue that causes the problem. the circuit board in an external enclosure or a sealed external HDD fixes the issue.

I recently installed 4 x 3TB seagate hard drives into a Mac Pro built in 2008. I was able to format and create a RAID5 with my existing RAID card BUT I am only able to access 2.2TB per drive instead of closer to 3TB as I had expected to see. Is there a 3rd Party RAID card that increases capacity assuming my existing Apple RAID card is the problem? Or can the Apple RAID card be updated? Is there a BIOS flash to be accessed?:confused: Or could there be another solution?
 

slughead

macrumors 68040
Apr 28, 2004
3,107
237
I think it my have been defective. Attempting to connect the same drive with the same adaptor to a Windows 7 box didn't work either, reporting the USB device was not recognized.


Go to seagate's website and get it swapped out for free ( may have to pay shipping there). 3TB drives are prone to failure, seems most likely at this point.

I have a 3TB drive which is working fine as a time machine backup btw.
 

partsoven

macrumors newbie
Oct 11, 2012
1
1
Found the fix

http://knowledge.seagate.com/articles/en_US/FAQ/207851en

The drive will need to be reformatted. Reformatting the drive will erase all data on the drive, so you should copy any data that is on the drive to a different drive before formatting.
To reformat the drive in MacOS X:
Open Disk Utility.
Choose Go in the Finder Apple menu (at the top of the screen).
Select Utilities.
Double-click the Disk Utility icon.
Choose the Seagate drive in the left window. If the drive is not showing, see step 3 below.
Choose the Partition tab in the right side of the Disk Utility window.
In the drop-down menu that says "current volume scheme", select one partition.
Press the Options button and select Guid Partition Table.

Change the Volume Format to MacOS Extended.
Click Apply.
Warning: This operation will erase all data on the drive, so before you continue, verify that any data on the drive is backed up somewhere else.
Click Partition. At this point, the volume dismounts from the desktop and the drive is partitioned and formatted.
Note: When Volumes are created, Time Machine may open, asking if you would like to use the volume for backups. Click Cancel to proceed.
If the partition fails on Leopard, see the special instructions below, in step 3.
The drive may go to sleep on its own. If it does, you can download a utility to prevent the drive from the link below. Keep in mind the drive will still be controlled by the MacOS power management features, which are set in Mac System Preferences.
Warning: Connect your FreeAgent drive to your Mac and wait for it to mount on the desktop before using the following utility.
Download the FreeAgent Go sleep disable utility's enclosed DMG file to your desktop.
Make sure the FreeAgent drive is connected to the Mac and mounted on the desktop.
Double-click the file to start the install process.
Follow the onscreen instructions to install.
During the install, the utility performs the sleep disable function, so no further steps are needed once the installation completes.
Note: If the drive is put on a Windows computer and the sleep time is adjusted with Seagate Manager, then this utility can be installed again on the Mac to disable the sleep function.
Make sure your computer can run your drive off a single USB cable. Some older Macintosh laptops do not provide enough USB power to run an external 2.5-inch drive and so the drive will not be detected at all in that case. If you encounter problems with this, there are a few options.
If this is a newly purchased drive, you may want to work with the place of purchase to exchange this drive for a FreeAgent Go for Mac, which runs on Firewire.
A special Y-Cable can be used to plug into two USB ports to draw additional power, if two ports are available. These cables can be purchased through many popular online retails and should have 1 - Mini USB B port (male) and 2 - USB A ports (male).
Use a powered USB hub which plugs into an electrical outlet and should provide enough power to run the drive.

Special instructions if erase fails on Leopard / Snow Leopard.
Leopard (Mac OS X - 10.5.x) and Snow Leopard (Mac OS X - 10.6.x) seem to be currently having problems reformatting external drives. This is a common issue on Leopard/Snow Leopardthat is seen on most brands of drives.
Note: This is not a problem with the external drive itself. Rather, it is an issue with the Disk Utility included in Leopard/Snow Leopard.
Suggestions: If partitioning/formatting the drive in Disk Utility fails, there are three options:
Ensure that any/all installer (DMG) files are dismounted before trying to prepare an external drive. Simply drag these files to the Trash to proceed.
Partition the drive using the OS install CD.
Insert your Operating System install DVD into the CD/DVD drive.
Restart your Mac.
Hold down the Option key while the Mac is rebooting.
Choose the "OS X install Disk" option.
Choose your preferred language.
Choose "Utilities > Disk Utility" from the top-menu.
Follow partition and formatting instructions from step 1-C.
If the Disk Utility Partition option fails, it may be necessary to move the external drive to a Windows system to repartition and reformat it. Click here to launch a video showing how to prepare an external drive using Windows Vista, or here for step-by-step instructions for Windows XP, or here for step-by-step instructions for Windows 7 / Vista.
Additional Information: Do not try to use the reformatting tutorial script that comes on the OneTouch 4 drives, as this script was designed for Mac OS X 10.4 (Tiger) and will not work properly on Leopard.
Note: Viewing of Video Tutorials Requires the following:
A screen resolution of at least 800x600
Javascript Enabled in your Browser
Adobe (Macromedia) Flash Player be installed on your system
 
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hfg

macrumors 68040
Dec 1, 2006
3,621
312
Cedar Rapids, IA. USA
I just added a 3TB Seagate drive to my 2008 3,1 Mac Pro with no problems. The drive is a ST3000DM001-9YN166 Rev. CC4B as reported in about-my-mac and is mounted in Bay 4.

FWIW:
I replaced a pair of older 1TB WD drives configured as RAID-0 with the new 3TB Seagate.
Using DiskSpeedTest:
The RAID-0 pair was showing 138 MB/s write and 141 MB/s read.
The single 3TB drive is showing 155 MB/s write and 153 MB/s read.
 

Tesselator

macrumors 601
Jan 9, 2008
4,601
6
Japan
I just added a 3TB Seagate drive to my 2008 3,1 Mac Pro with no problems. The drive is a ST3000DM001-9YN166 Rev. CC4B as reported in about-my-mac and is mounted in Bay 4.

FWIW:
I replaced a pair of older 1TB WD drives configured as RAID-0 with the new 3TB Seagate.
Using DiskSpeedTest:
The RAID-0 pair was showing 138 MB/s write and 141 MB/s read.
The single 3TB drive is showing 155 MB/s write and 153 MB/s read.

Something is strange there. In single drive I get like 175MB/s average (across the platter) and around 190MB/s sustained for the 1st 65% of the platter, and like 220 to 230MB/s burst.

In RAID0 with those drives I get 400MB/s sustained, 500MB/s burst, and bout 370MB/s "average".
 
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