Questions tagged [core-storage]

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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OS volume shows as type 'FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF'

Yesterday, I have tried to delete an Ubuntu partition. Since, my Mac (13", MBPro mid-2014) doesn't boot. Now, I boot on Mac OS copy with an USB. i follow different subject of this forum (like this : ...
Nicolas Lorand's user avatar
40 votes
8 answers
70k 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 ...
Christian's user avatar
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55 votes
6 answers
23k 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 ...
FishesCycle's user avatar
17 votes
16 answers
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?
Aron Rotteveel's user avatar
5 votes
1 answer
4k views

iMac disk partion FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF and fusion drive unlinked

I was trying to uninstall linux mint and was trying to restore the partitions back to one. Somehow I ended with the one of the partition labeled FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF. This are the ...
user217155's user avatar
3 votes
4 answers
2k 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 ...
Graham Perrin's user avatar
9 votes
4 answers
85k 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 ...
Eric's user avatar
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5 votes
2 answers
13k 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 ...
maze's user avatar
  • 151
18 votes
3 answers
6k views

Difference between enabling Time Machine's "Encrypt Backups" option, and encrypting 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" ...
jtbandes's user avatar
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3 votes
1 answer
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Remove Linux partition on Mac. CoreStorage problems

I have a Macbook pro 2015 with a 256 GB SSD and a Linux partition. I would like to remove the partition. Following the steps written in here, I got stuck in the Modify step. Once I execute the command ...
Alex C.'s user avatar
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2 votes
2 answers
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How do I regain unaccessible free space after a failed Boot Camp install on a non-Fusion drive?

Firstly - I know this has been answered, but I am hoping for a more broken down answer, as I am not quite so technically minded, but I can follow instructions! So in summary I have tried to install ...
Christopher Heyworth's user avatar
15 votes
3 answers
106k 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 ...
László's user avatar
  • 461
12 votes
1 answer
16k 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 ...
JasonGenX's user avatar
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10 votes
6 answers
21k 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 ...
Jess Bowers's user avatar
7 votes
4 answers
17k views

APFS with external hard drives (non SSD)

I bought a new external hard drive for my Mac. What is the best file system in 2021 to format the external hard drive? I would like to encrypt the hard drive and I only use it with Macs so I don't ...
T. Walker's user avatar
5 votes
1 answer
2k 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, ...
DavidA's user avatar
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3 votes
3 answers
9k 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 ...
Milliways's user avatar
  • 7,992
3 votes
2 answers
7k 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 ...
timvickers's user avatar
2 votes
3 answers
14k views

I can't shrink my OS X Yosemite partition [duplicate]

I recently reformatted my machine and am trying to shrink my OS X partiton to make room for a linux partition, following instructions at http://www.makeuseof.com/tag/install-linux-macbook-pro/ . I am ...
qmlowery's user avatar
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1 vote
1 answer
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My Fusion Drive Partitioning Seems Wrong/Strange/Wonky

See below for diskutil list of my 3TB fusion drive (iMac 27" late 2014) running High Sierra: I assume disk0 is the HD and disk1 is the SSD, and disk2 is the virtual combo that is mounted as my &...
P Dolch's user avatar
  • 61
1 vote
1 answer
453 views

Partition of harddisk lost/unusable

I'm using OS X Yosemite - version 10.10.2. I have 1.12 TB fusion drive on my system. Recently I wanted to make a partition on my system, while making the partition on the system using disk utility ...
hokts's user avatar
  • 13
0 votes
1 answer
2k views

Missing Space on Drive using Core Storage after Boot Camp Assistant Failure

Using Boot Camp Assistant, I started to create a 50 GB partition, but it hung on partitioning. After waiting about 30 minutes without the progress bar moving, I quit the Boot Camp Assistant, thinking ...
Alan Norton's user avatar
0 votes
1 answer
996 views

Apple-provided software to measure or estimate the CPU load associated with Core Storage

With Mac OS X 10.7 (Build 11A411) alone, or with Xcode 4.1: Q: is there a way to accurately measure, or at least estimate the CPU load associated with Core Storage? A graphical view of load on a ...
Graham Perrin's user avatar
12 votes
2 answers
3k 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 ...
Lanny Heidbreder's user avatar
10 votes
3 answers
8k 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 ...
BladeCity's user avatar
  • 101
7 votes
2 answers
12k views

Is it OK for Time Machine to take a long time to decrypt a freshly formatted encrypted disk?

I'm new to Time Machine. I just this week got an external hard disk and am starting to use it. My Time Machine backups were spending a significant amount of time in the encryption phase. Upon reading ...
firebush's user avatar
  • 345
5 votes
1 answer
2k views

Can't resize partition: "You can't perform this resize unless it has a booter"

I have an external 1TB disk that I use for Time Machine backups that I temporarily added a second 100GB partition to. After deleting the partition, though, I can't reclaim the free space. Disk Utility ...
Tom Martin's user avatar
4 votes
1 answer
4k views

How do I re-fuse an unfused Fusion Drive, ideally without formatting?

I have a 5k iMac with a Fusion Drive. I had trouble with macOS, so I reinstalled it, and restored from a Time Machine backup using Migration Assistant. After that, the system has been very slow, and ...
Kartick Vaddadi's user avatar
4 votes
0 answers
117 views

Accidentally overwrote encrypted external drive (Mac OS)

So I was rushed (and being careless) and accidentally copied about 80 MB of a Raspberry PI image (SD card formatted extfs) over my external USB drive (4TB) that was formatted and encrypted (using Disk ...
Adam Barrow's user avatar
4 votes
1 answer
5k views

How to add free space to a Logical Volume Group? (Resizing Partitions)

I have two CoreStorage volumes on disk, one is 200GB the other is 50GB. I want to make the 1st 125GB and the second one 125GB. Currently I have been able to use the diskutil cs resizeStack command to ...
RefuX's user avatar
  • 143
3 votes
2 answers
2k 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 ...
almaz's user avatar
  • 131
3 votes
3 answers
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 ...
daveMac's user avatar
  • 213
3 votes
1 answer
2k 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 ...
Rob Starling's user avatar
2 votes
1 answer
2k 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 (...
RHPT's user avatar
  • 708
2 votes
1 answer
16k 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 your ...
fanjavaid's user avatar
  • 121
1 vote
1 answer
6k 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: ➜ ...
swalkner's user avatar
1 vote
1 answer
854 views

Can't delete partitions after attempting BOOTCAMP on my iMac 5k

I recently tried to install a bootcamp instance of Win 7. The install failed for some reason. This left me with a partition that I can not access via Disk Utility If you notice..the +- can not be ...
Omaer Sheikh's user avatar
1 vote
3 answers
3k views

Clear free space in Disk Utility

So I recently removed Windows 7 from my iMac, but Bootcamp didn't let me do it. I used Disk Utility instead. The old Windows 7 partition now shows up as free space. I want to reinstall Windows 7 again ...
Deuce55's user avatar
  • 13
1 vote
1 answer
2k views

Disk Utility not letting me partition my SSD or modify the current ones

Just yesterday I finally got my hands on a MacBook Pro in which I was planning to install Ubuntu and Windows aside from OS X for studying purposes. I was barely beginning by partitioning the disk, or ...
Alvaro Nicoli's user avatar
1 vote
1 answer
2k views

Crashed when creating a partition - now missing drive space!

Just a couple of hours ago, while I was taking a GNU course, I decided to create a partition on my SSD to have ubuntu installed, meanwhile the disk utility was doing that, suddenly it just crashed and ...
David M's user avatar
  • 11
1 vote
1 answer
840 views

Reclaim SSD space from deleted partition

I have a very similar problem to one that was answered here, but I don't know how to apply the answer to my mac. MacBook Pro 15", Late 2013, 2.3GHz/16GB/512GB, Yosemite 10.10.3 I was attempting to ...
user148341's user avatar
1 vote
2 answers
809 views

Logical Volume Group 17gb "Available Space"

Can anyone help explain why there is 17 GB worth of free space on my LVG I can't seem to do anything with this space. Is there anyway to fix this? I have already reformatted the disk then cloned the ...
Arron's user avatar
  • 11
1 vote
1 answer
593 views

Is it possible to have multiple filevault2-activated partitions on one disk?

What I would like to have: A disk with the following systems on it: OS X 10.8 (FV2-encrypted) OS X 10.9 (FV2-encrypted) Windows 7 When I try to start FV2-encryption on my secondary partition, OS X ...
n1000's user avatar
  • 7,724
1 vote
1 answer
4k views

CoreStorage Volume not detected

I had a Linux/OS X 10.11 dual boot configuration and wanted to remove the Linux partitions. I managed to remove them without any issue but when trying to merge the free space with the OS X partition ...
tutzeroone's user avatar
1 vote
2 answers
317 views

Why can't I delete the second partition

So I was playing around with Disk Utility today. I created a second partition. Format is Free Space. How do I undo this? As in, I want to have just one primary partition "Macintosh HD" I've tried: ...
Christian Fazzini's user avatar
0 votes
1 answer
278 views

Lost hard drive space to Boot Camp

Boot Camp caused ~200 GB of my 750 GB HD to disappear and I cannot re(un)-partition it through Disk Utility and when I try to reformat the storage through the terminal using: diskutil cs resizeVolume ...
Ethan Allnutt's user avatar
0 votes
1 answer
846 views

How do I resize an ex-CoreStorage volume?

I've got a Macbook Pro Retina (with the PCIe drive ‘blade’, instead of a traditional 2.5" laptop drive). I've recently upgraded the internal drive from 500GB to 1TB, and dd'd the old drive over the ...
ELLIOTTCABLE's user avatar
0 votes
2 answers
4k views

How do I repartition my Mac to get rid of my dual boot setup?

I setup dual boot on my Mac (with Ubuntu) and want to get rid of it. The Disk Util GUI shows me: However attempting to remove the disk0s4 or disk0s5 partitions results in: Could not unmount ...
Peter's user avatar
  • 103
-2 votes
1 answer
1k views

Hardrive will not mount after deleting Linux partition. Can’t boot into Mac OS X [duplicate]

I tried to delete a Linux partition on my hard drive. My hard drive was no longer bootable and the type turned into FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF. I tried to follow some of the other ...
Rahul Ravisankar's user avatar