Apple Core Storage (sometimes referred to as coreStorage or CoreStorage) maintains a world of virtual disks that can provide the user with flexibility in allocating their hardware.

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46
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8answers
18k views

Can I make a DIY Fusion Drive?

I have a Mac Mini with two drives: a 256GB SSD and a 500GB HDD. From what I've read, the new Fusion Drive does all of it's magic in software, using the Core Storage APIs. Can I get my setup to ...
23
votes
5answers
36k views

Resizing or expanding a CoreStorage volume

I bought a new SSD with 750 GB and made two partitions: 600 GB and 150 GB. The smaller one was thought to be a Bootcamp partition one day, but to date it was just another unused partition. When I ...
16
votes
16answers
3k views

Apart from being able to encypt an entire volume, what are the other differences of FileVault 2 over FileVault?

Does FileVault 2 in Lion have any other differences compared to the old version, FileVault in previous releases of the system? Are there any additional benefits to using the new version?
14
votes
3answers
14k views

How can I rename a Logical Volume Group?

I have noticed that while I can safely change the name of the Logical Volume (LM Volume) in /Volumes (currently: Apple SSD), I cannot find a way to change the name of the Logical Volume Group ...
12
votes
1answer
15k views

Can't ever remove partition?

Running Mountain Lion. I added a partition with Disk Utility and then had second thoughts about it. I'd like to remove the partition i created, MacSSD2 and hand over its space back to MacSSD. As you ...
12
votes
2answers
2k views

Will FileVault 2 wear out my SSD faster?

I'm considering using FileVault 2 when I upgrade to Lion. Though my understanding of it is weak, it seems as though it shouldn't really increase the number of reads or writes per disk operation ...
12
votes
3answers
58k views

How can I delete a partition (coreStorage logical volume?) from the Terminal?

I finally understood why Disk Utility will not change the partitions on my HDD, even though I added the most recent one myself (maybe significant: to test Yosemite DP) with it. Now I see it says it ...
9
votes
3answers
4k views

What happens when you remove (or lose) the SSD from a Fusion Drive?

After storing data on a Fusion Drive, is it possible to downgrade your Mac to use the hard drive (HDD) by just removing the solid state drive (SSD)? In particular, I was wondering what happens when ...
8
votes
5answers
18k views

DIY Fusion Drive: Adding Recovery HD to a CoreStorage Volume Group

After creating a "DIY Fusion Drive" using the methods below in 10.8, I'm now wondering how to add a RecoveryHD partition to the internal drive. Here's what I did to create a Logical Volume Group ...
5
votes
3answers
17k views

Unable to reformat/repartition CoreStorage logical volume (Fusion drive)

I created a fusion drive on my MacBook Pro running Mountain Lion and it worked like a charm for a while, but it somehow got corrupted. Now I am unable to reformat or repartition the whole thing. ...
4
votes
4answers
58k views

Restore Macintosh HD to its original partition configuration

I seem to have badly botched a Boot Camp installation of Windows 8.1. I used Boot Camp Assistant to create a 200 GB BOOTCAMP partition on my 1 TB Fusion Drive. I then rebooted and failed to install ...
4
votes
6answers
13k views

How can I verify that a DIY Fusion Drive is working as it should?

I installed an SSD in my 2011 Mac Mini to run alongside the stock 500GB HDD. After carefully reading through a number of tutorials, I used Terminal to merge them into a single "Fusion Drive". I cloned ...
3
votes
4answers
1k views

What techniques for disk, volume and file system management are possible with OS X, but troublesome within Disk Utility?

In the past, Disk Utility was the best starting point for the vast majority of disk-related tasks. As technologies within (or possible with) OS X have developed – without equal development of Disk ...
3
votes
3answers
3k views

Why does my 3TB Seagate HD keep formatting as a Logical Volume Group

This is really annoying. I have a brand new Seagate 3TB 7200 RPM hard drive that I am trying to format/partition in Disk Utility. Every time I change any settings or erase the drive, it changes it to ...
3
votes
2answers
1k views

What is the layout of a real Apple supplied fusion drive?

Would someone who has a fusion drive that they bought directly from Apple please provide diskutil output sufficient to describe the choices they made? I've seen lots of different sets of advice for ...
3
votes
1answer
144 views

DIY Fusion drive with 3 drives

Is it possible to build a DIY Fusion drive using 3 drives - 2 HD's and 1 SSD? Will the Fusion machinery optimise on three levels i.e. SSD, then fast HD, then slow HD? I have a mid 2011 27" iMac, ...
3
votes
1answer
300 views

I erased the partition where Windows 10 was previously installed. How can I merge it with my OS X partition?

So I started up Disk Utility and erased my BOOTCAMP partition and set the format to OS X Extended (Journaled). This is how my partitions look like now: As you can see, I have a BOOTCAMP partition ...
3
votes
1answer
269 views

re expand a partitioned disk

The internal disk of my Mac book pro is partitioned as follows: % diskutil list /dev/disk0 #: TYPE NAME SIZE IDENTIFIER 0: ...
3
votes
1answer
1k views

What's the difference between enabling Time Machine's “Encrypt Backups” option, and encrypting my disk from Disk Utility?

I'm setting up Time Machine backups on a new external hard disk. I chose to first encrypt the disk via Disk Utility: But I also see these options: Is there any difference between an "Encrypted" ...
3
votes
1answer
2k views

OS X Mountain Lion does not boot after the creation of a Fusion Drive

I have followed a guide to set up the core storage logical volume to use one SSD and one HDD. Since then, I have encountered multiple errors such as: 69822 Couldn’t rediscover disk after operation ...
3
votes
1answer
3k views

Restoring Fusion Drive after error on partition erase

I think I'm lost and need some help with my Fusion Drive. I have new iMac Retina 5k with 3TB Fusion Drive and preinstalled Yosemite. Things I did so far: I was working on my iMac and had ...
3
votes
1answer
577 views

Is there a way to change order of physical disks in Corestorage

I upgraded existing system to a "Fusion drive" - corestorage volume - consisting of existing 300GB HDD and new 120GB SSD. Instead of creating a new corestorage drive I went with the route of ...
3
votes
1answer
4k views

Name-error when formatting NTFS on OS X 10.8.4 using “diskutil” (Terminal)

I have a 2011 Macbook Pro 13 inch - OS X 10.8.4 (Mountain Lion), which i upgraded with a SSD. I installed the original HDD as second drive instead of the optical. I need to change the filesystem for ...
3
votes
0answers
521 views

Is it safe to convert Core Storage partition to HFS+?

I just got my new Macbook Pro, I tried to make two new partitions using Disk Utility but I could only create one. After googling I found out that I can't create more than one additional partition in ...
3
votes
2answers
4k views

OS X Partition not resizable

3 weeks ago I installed Yosemite public beta onto a brand new Macbook Air which arrived with Mavericks pre-installed. To carry out the installation I created a new partition for Yosemite and so had ...
2
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2answers
2k views

CoreStorage: what does LVG status 'offline' and PV status 'checking' mean and how can it be fixed?

I converted a partition to a CoreStorage volume using this command: sudo diskutil cs convert disk0s2 -passphrase test123 Now when I run `diskutil cs list' the output shows that I still only have a ...
2
votes
1answer
10k views

diskutil shows Macintosh HD is missing (with Recovery HD occupying the entire space)

So yesterday I managed to screw up my iMac 2012 (with Fusion Drive) by installing the Mac OS X 10.10.2 update... The installation stalled and when I tried to restore from an external drive using Time ...
2
votes
1answer
1k views

Problem after erasing the HD of a brand new Mac (OS X Yosemite) with Disk Utility

I cannot reinstall OS X Yosemite now, as there's no hard drive I could see. I had erased the HD with the idea that it will create a new partition but it didn't, so now I can't see a hard disk on ...
2
votes
1answer
676 views

Messed up 1TB Fusion Drive Partitions (on iMac 5K)

Alright, so I did something stupid today, and I really need some help right now… So kinda like the situation in this post I think I messed up the Fusion Drive on my 1TB iMac (with BootCamp), I messed ...
2
votes
3answers
3k views

How can I resize a partition on OSX 10.10.5

I have a Mac with OS X 10.10.5 on a HD which had 4 partitions. Using Disk Utility I deleted one of the 4, intending to slightly grow the 3rd (containing the OS), leaving space for a new partition to ...
2
votes
2answers
10k views

How do I remove unused partition (El Capitan)?

I have a partition that I no longer use. I've tried erasing with the disk utility GUI, but when I try to remove (with the '-' minus button on the partition view) this feature is disabled. I've also ...
2
votes
1answer
271 views

Fusion drive unavailable after HD erase

I wanted to erase the 3 TB Fusion HD on my iMac in order to install a clean system and start from scratch. The erase went fine except right at the end when it said something about core storage... ...
2
votes
1answer
2k views

Fixing a failed full disk Core Storage encryption

I selected the encrypt disk option from the Finder initially, but after several days without progress (I checked diskutil cs list and it didn't show that it was either encrypted or converting) I ...
2
votes
1answer
1k views

Can I have both a case-insensitive system volume and a case-sensitive volume within an encrypted CoreStorage volume?

( seems possibly related to Is it possible to have multiple filevault2-activated partitions on one disk? ) I have a MBP with a single internal SSD and I'd like: to have everything on the disk ...
2
votes
1answer
1k views

What's the significance of non-checkpoint transactions in Core Storage?

Often in output from fsck_cs(8) – typically in the window of Disk Utility in Lion and Mountain Lion, whilst verifying or repairing something in Core Storage world: Incorporate 1 newer non-checkpoint ...
2
votes
1answer
228 views

Expanding a Fusion Drive partition

I created a partition on my Fusion Drive when I first purchased my iMac running Yosemite, and I would like to now resize that drive ("Data" in the screenshot below), but Disk Utility doesn't allow it ...
2
votes
2answers
286 views

Resize FusionDrive to fill empty space?

Context: I wanted to install Windows 8 onto my Mac by repartitioning my FusionDrive. Using the partition BootCamp provided didn't work, so I found a "solution" on Apple forums to create empty space ...
2
votes
1answer
5k views

How to fix the error: “This disk doesn’t contain an EFI system partition”?

I get the following error and cannot start Bootcamp after accidentally deleting the EFI-partition of my main drive. This disk doesn’t contain an EFI system partition. If you want to start up ...
2
votes
2answers
253 views

My SSD Drive has been converted to a Core Storage drive and cannot be erased/reformatted?

I put an SSD drive into my macbook pro. I should say that this drive hadn't been formatted and was a bootable drive with Yosemite OS on it, taken from another macbook pro... I booted the system up in ...
2
votes
2answers
4k views

Understanding kernel panic error log

My MacBook Pro worked all normal when all of a sudden it went black. It tried to reboot itself but immediately produced a kernel panic. From then on I was never able to boot again. I could only enter ...
2
votes
2answers
2k views

How do I see disk usage within a Fusion Drive (CoreStorage Logical Volume)?

I just created a "Fusion Drive" on my MacBook Pro by following "How to make a Custom CoreStorage Drive in OS X". It was created with a 256GB SSD and 320GB HD, with the SSD set as the "primary" disk ...
2
votes
1answer
1k views

FileVault (CoreStorage) + Linux partition

Quick question here. I'm not really familiar with the requirements of CoreStorage so I'd like to confirm with you guys before I start working. I'm currently running OSX Lion on my MacBook Air, with ...
2
votes
3answers
203 views

Missing space on Fusion Drive (partition problem)

I know this or similar problems have been discussed, but (to be honest) I can't see the trees for the wood. I tried to create a partition on my fusion drive (1TB Hd + 240 MB SSD). No partition was ...
2
votes
1answer
107 views

Cannot partition Macintosh HD

Pre P.S. From what I read online, sharing your UUID is not really a security issue, but if I just basically shared my social security number, please do tell. Before I ask this, I'm a PC person and ...
2
votes
1answer
1k views

CoreStorageFamily::unlockVEKs() failed to unwrap the vek, status = e00002bc

I have a filevault2 disk with two partition. One is the boot partition, the other contains data, both are encrypted. Today, after installing the latest 10.8 update (10.8.4 I guess), the computer ...
2
votes
0answers
316 views

How do I troubleshoot appalling write performance on DIY Fusion Drive? [closed]

I recently bought a 120 GB OCZ Vertex 3 and stuck in my 2009 Macbook White, together with a optibay-adapter for the old 500 GB HDD and configured them as a corestorage "fusion drive" by using the ...
1
vote
2answers
6k views

Disk Utility Error “Storage system verify or repair failed”

Installed Lion on a brand new HDD. Boots fine, but when I run Disk Utility on the Media, it reports Verifying partition map for “WDC WD10JPVT-16A1YT0 Media” Checking prerequisites Checking the ...
1
vote
1answer
110 views

What's wrong with my Fusion Drive?

I'm having weird issues with my internal Fusion Drive. Symptoms: It gave itself a new cryptical name, and I can't change it back In most cases I cannot install new software anymore (e.g. I cannot ...
1
vote
1answer
422 views

Unable to restore/reinstall/erase from recovery

I've just tried to install the El Capitan GM, which failed half way through with the error "This Core Storage operation is not allowed on a sparse logical volume group" and gave me the option to ...
1
vote
1answer
2k views

Fusion Drive seems to be messed up

I felt that my iMac late 2012 became pretty slow, above all after login. Now when I look into disk utility, it seems that my disk doesn't behave as Fusion Drive any more: An output from terminal: ...