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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

Sep 28, 2013 8:30 AM in response to aaaashy

Lion and above have a small (under 1GB) Recovery partition. CCC just asks to make sure if you want to include one on your other drives (recommended) so you can use it as a small mini OS to use a trimmed down limited set of programs.


Having a clone from say 10.8.3 or earlier would be a better route. Saving that ML installer you got say back in 10.8.0-10.8.3 would also be handy to have to do a clean install and have your own 20GB system - and not update it past 10.8.3 (hence the usefulness of those combo updates for manually install and reinstalling, rather than automatically which will take you to 10.8.5 again).

Dec 7, 2013 7:57 AM in response to Frank Lowney

All the earlier Mac Pro through the 4,1 2009 model can boot from the 10.6 "Full Retail" DVD, which is still available from the Apple Online Store for US$20.


The 5,1 models (2010 and 2012) require custom 10.6.4 as a minimum. So they can RUN 10.6.8 if you have it on an old drive, but they cannot BOOT from the Full Retail DVD, (which contains 10.6.3).

Dec 7, 2013 8:15 AM in response to Grant Bennet-Alder

So what does this mean in practice, say you have a 3TB or 4TB drive in 10.8.5 ?


I replaced a non-startup drive holding my iTunes library which was low on space with a 4TB WD black drive some weeks ago - a bit noisy like my smaller 750GB blacks but seems to be working ok for the intended usage - the black is probably overkill for itunes streaming to AppleTv but it was on offer.


Disk Utility indicates it's formatted as GUID partition table, so anything to be wary of?


I ask primarily as ML is behaving oddly - peculiar finder oddities and a few other things that make me think I've either got a dodgy logic board or ML is corrupt.


AC

Dec 7, 2013 8:55 AM in response to Grant Bennet-Alder

Grant Bennet-Alder wrote:


This is NOT a subtle problem. You can't do ANYTHING with it -- the drive is useless and you are stuck.


The problem is the new Drive gets configured as a Logical Volume group.

When you say I can't do anything with it I don't follow but am undoubtedly missing something. I've been using it for a few weeks now and have another unopened.


User uploaded file


and


User uploaded file


AC

Dec 7, 2013 9:00 AM in response to Grant Bennet-Alder

Grant Bennet-Alder wrote:


Alley_Cat-


YOU have dodged this bullet completely. [I dunno how or why.]


Users with this problem end up with a >2.2TB+ Logical Volume group as the only item on the drive and cannot erase or create ANY Volume on it. The drive is dead in the water.

Yikes and phew!


Can the dead drive be salavaged and reformatted using 10.9 or earlier ML installations or on a Windows system?

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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