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Disk Utility defaulted to Logical Volume Group format for new 4TB HDD and won't let me change to GUID. Is that a problem?

I just installed a 4TB HGST HDD in the 4th bay of my mid-2010 mac pro (2.8 GHz Quad-Core Intel). I formatted the drive using Disk Utility's "Erase" tab as Mac OS Extended Journaled and the drive seems to be working fine (set up as Time Machine backup). It is recognizing the full 4TB capacity and the first backup in TM took a long time but all the files are there. However, my understanding is that all drives intended for use solely in my mac should ideally be formatted to GUID. The problem is that Disk Utility formatted the drive to a Logical Volume Group/Logical Partition, so it's not allowing me to change the format type now i.e. when I go to the "Partition" tab in Disk Utility, all of the options are greyed out. Also, the RAID tab does not appear for this drive as it does for the other three 1TB drives installed.


So my ultimate question is this - is it a problem that I can't reformat to GUID? If so, why is it a problem and how do I fix it?


Thanks!

Mac Pro, OS X Mountain Lion (10.8.4)

Posted on Aug 19, 2013 12:23 AM

Reply
76 replies

Jan 26, 2017 12:41 PM in response to jake10e

By the way guys, just so you know the EASIEST way you fix this WITHOUT having to find a Lion installer and copy it to a USB drive or digging up a Snow Leopard Install DVD (which doesn't work with Mac Pro 5,1 models because they require 10.6.4). Anyway I resolved this issue in about 40 seconds by;


Go to "Apple Menu > About This Mac > More Info… > System Report > Storage"


Find the LVG UUID (Logical Volume Group UUID) NOT the "Physical UUID" "Volume UUID" or anything else. It's a bit confusing, because the UUID you need will sometimes be the one in the middle.


The Logical Volume Group UUID will look like this; ########-####-####-####-############ (the # symbols represent letters or numbers)


Once you find the UUID, launch Terminal.app from "/Applications/Utilities" and simply type;


diskutil cs delete ########-####-####-####-############


And hit return!


Replace ########-####-####-####-############ with the UUID found in System Information under Storage. You can just type "diskutil cs delete" then copy and paste the UUID (make sure there are no extra spaces before or after the UUID)


That's it!


I hope that helps!

Jan 26, 2017 6:29 PM in response to uhmyearightok

uhmyearightok wrote:


By the way guys, just so you know the EASIEST way you fix this WITHOUT having to find a Lion installer and copy it to a USB drive or digging up a Snow Leopard Install DVD (which doesn't work with Mac Pro 5,1 models because they require 10.6.4).

FYI the 2010 Mac Pro 5,1 models CAN boot from the retail Snow Leopard disks, either 10.6 or 10.6.3. I know this from personal experience, because that was how I installed Snow Leopard on my 2010 refurb Mac Pro, which came with Lion installed and did not include the 10.6.4 disks. I made some calls right after getting it because I did not want to run Lion. I was told by a very knowledgeable guy in Apple Support that the retail disks would work, and he was absolutely correct.


I still format new drives using the Snow Leopard version of Disk Utility.

Jan 28, 2017 7:08 AM in response to jake10e

I own two 5,1 (2010, not 2012) Mac Pro's and they do NOT boot from the 10.6.3 retail DVD (they never have been able to since I first bought them) and unfortunately I no longer have the original 10.6.4 Mac Pro System Restore DVD that they came with so I would like to know very much how you were able to do this.


I actually tried this pretty recently, about two weeks ago and when I inserted my Snow Leopard retail DVD into the Mac Pro it gets to the point where it shows the grey screen with Apple logo and you can hear it reading data from the disc very rapidly, as if it's trying to boot but then it just goes quiet and no matter how long I waited it was just stuck there. I'm planning on ordering a 2009 Mac of some sort just to use it to make a 10.6 installation, update it to 10.6.8, and CCC it over to another drive to make a bootable drive for my other 2010 Macs.


Unfortunately I have to actually buy a new computer for this since I lost most of my older Macs in a fire. (Many of my older Macs, including many PowerPC macs were in the same room as my original OEM Mac Pro restore discs) 😟 which is why I'm having this issue now. I refuse to update to 10.12 lol

Aug 19, 2013 1:13 AM in response to kaz-k

kaz-k, here's what it says (disks 5 and 6 are external LaCie drives):


/dev/disk0

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *4.0 TB disk0

1: EFI 209.7 MB disk0s1

2: Apple_CoreStorage 4.0 TB disk0s2

3: Apple_Boot Boot OS X 134.2 MB disk0s3

/dev/disk1

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *1.0 TB disk1

1: EFI 209.7 MB disk1s1

2: Apple_HFS Macintosh HD 2 999.9 GB disk1s2

/dev/disk2

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *1.0 TB disk2

1: EFI 209.7 MB disk2s1

2: Apple_HFS Macintosh HD 3 999.9 GB disk2s2

/dev/disk3

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *1.0 TB disk3

1: EFI 209.7 MB disk3s1

2: Apple_HFS Macintosh HD 999.3 GB disk3s2

3: Apple_Boot Recovery HD 650.0 MB disk3s3

/dev/disk4

#: TYPE NAME SIZE IDENTIFIER

0: Apple_HFS 4 TB Time Machine *4.0 TB disk4

/dev/disk5

#: TYPE NAME SIZE IDENTIFIER

0: Apple_partition_scheme *320.1 GB disk5

1: Apple_partition_map 32.3 KB disk5s1

2: Apple_Driver43 65.5 KB disk5s2

3: Apple_Driver_ATA 65.5 KB disk5s3

4: Apple_FWDriver 114.7 KB disk5s4

5: Apple_HFS LaCie 320.1 GB disk5s6

/dev/disk6

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *1.0 TB disk6

1: EFI 209.7 MB disk6s1

2: Apple_HFS LaCie 1TB 7-2013 999.9 GB disk6s2


What do you think?

Aug 19, 2013 1:47 AM in response to jake10e

This is a problem with 3 TB + drives and ML. This indicates a fusion drive scheme:

/dev/disk0

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *4.0 TB disk0

1: EFI 209.7 MB disk0s1

2: Apple_CoreStorage 4.0 TB disk0s2

3: Apple_Boot Boot OS X 134.2 MB disk0s3



Type in terminal "diskutil cs list"


Post the output in your reply.



Edit: Misread the OP, this is your boot volume, not the TM 4TB volume. Disregard.

Aug 19, 2013 3:46 AM in response to jake10e

Using distutil from the command line you can work around the bug. It is more specifically an issue with OS X disk utility. Run "diskutil cs list," regardless, and post the output. There is a work around from the command line. There is also a program:

Coriolis Systems :: Products :: iPartition



Also, see the 'more like this' posting in the right pane:


Re: 4 TB Hard drive formatting default to Logical Volume Group

Aug 19, 2013 9:41 PM in response to nbar

nbar, I ran "diskutil cs list" as you recommended. Here's the output.


CoreStorage logical volume groups (1 found)

|

+-- Logical Volume Group B4BDA3F3-CBD5-461B-88BB-DEEAF3B0DA33

=========================================================

Name: 4 TB Time Machine

Status: Online

Size: 4000443056128 B (4.0 TB)

Free Space: 0 B (0 B)

|

+-< Physical Volume 82DBA846-61FE-4C97-9966-0773515D89DC

| ----------------------------------------------------

| Index: 0

| Disk: disk0s2

| Status: Online

| Size: 4000443056128 B (4.0 TB)

|

+-> Logical Volume Family 5C1924C0-C3F1-4040-B009-E1CA61C7147D

----------------------------------------------------------

Encryption Status: Unlocked

Encryption Type: None

Conversion Status: NoConversion

Conversion Direction: -none-

Has Encrypted Extents: No

Fully Secure: No

Passphrase Required: No

|

+-> Logical Volume 1CA55C12-9886-4F76-97DC-F3C9C852C471

---------------------------------------------------

Disk: disk4

Status: Online

Size (Total): 4000124280832 B (4.0 TB)

Size (Converted): -none-

Revertible: No

LV Name: 4 TB Time Machine

Volume Name: 4 TB Time Machine

Content Hint: Apple_HFS


What do you see? Thanks for your help!

Aug 19, 2013 9:56 PM in response to nbar

Also nbar, I checked out the similar thread you mentioned Re: 4 TB Hard drive formatting default to Logical Volume Group and saw that the user who posted the question returned his 4TB drive a went back to a 2TB...I really don't think I can do that. I run a photography business and I'm planning to run a 2TB "working" drive that will hold all of my in-process photos, a 1TB "archive" drive where I will store all of my final portfolio images, and a 480GB SSD as my "system" drive that will run all of my software, photoshop, etc. This 4TB drive is meant to back all of it up on an hourly basis, which is important since we're editing photos and designing albums all day and inevitably need to go back and find an original file. Then I have a 8TB external RAID5 (4 bay system) that will create a daily backup of everything as well. With people's wedding photos, I'm really striving for multiple layers of redundancy and protection.


I guess one of the main questions I have at this point is this whether partitioning my 4TB HDD with a GUID partition table is critical. I mean, the drive seems to be working okay. The full 4TB capacity is recognized and available, and Time Machine is backing up hourly (granted, there is only 2.2TB of data loaded on it currently...not sure what will happen as it fills up...). Do I even need to press the issue of GUID? What are the pros/cons of eventually reformatting it? What are the risks if I don't? Sorry for the questions - I'll admit that I'm not very technically inclined...I'm just trying to learn as fast as I can so I can protect my clients' images!

Aug 20, 2013 3:58 AM in response to jake10e

A safety net in case of problems is always worth considering!


And having 10.8.3 even just a small system image / partiton so you can format the drive and put it to use such as today - until a patch or new update is made available.


Apparently in trying to fix an issue with 3TB Fusion drives and Windows/Boot Camp no one bothered to test other setups and scenerios like us!

Sep 3, 2013 1:08 PM in response to aaaashy

The problem was noted here, and readers urged the Poster to report it as a Bug through the Genius Bar or AppleCare tech support. That was done, and Apple accepted the problem as a Bug Report. They later contacted the report filer and said they had re-created the problem, and discovered that it was a Bug introduced, probably in 10.8.4, while attempting to fix "over 2.2TB drive size" for Windows. A fix is supposed to be forthcoming. (Some of the rumor sites say there is a 10.8.5 being tested, but whether this fix makes the cut no one will be able to say until release.)


If you have a Mac that can run 10.5 or 10.6 from a DVD, or an old drive with a 10.7 Recovery_HD on it, you could use their Disk Utility to accomplish the job for you.

Disk Utility defaulted to Logical Volume Group format for new 4TB HDD and won't let me change to GUID. Is that a problem?

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