Apple's built-in disk management utility for the mac. Erases, formats, and restores volumes and drives.

learn more… | top users | synonyms

0
votes
1answer
112 views

Resizing Macintosh HD partition to use free space

I recently deleted a partition and have 60GB of free space. I would like for my main partition to use that, but whenever I go to resize it, I get the error "You can’t perform this resize unless it has ...
0
votes
0answers
18 views

Brand new 15in retina

I bought the mac then hooked up Time Machine and started restore to Mac HD. All was fine until the end when the backup from on 6 minutes to go for a couple of hours. No progress at all. So after ...
0
votes
0answers
31 views

What to do after mistakingly shrinking disk in Disk Utility?

I only had 1 volume on my hard drive. I tried to shrink it with Disk Utility - thinking it would resize the disk and the other space would be available to create another disk with. I didn't add any ...
1
vote
1answer
629 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 ...
9
votes
4answers
11k 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 ...
0
votes
0answers
120 views

Restore on new drive: Time Machine versus “Restore” via Disk Utility

I am about to install a new 240GB OWC Mercury Electra 6G (6Gb/s) SSD into the main drive bay of my MacBook Pro, moving the original Apple-installed 120GB 3G (3Gb/s) SSD into the optical bay using an ...
3
votes
5answers
18k views

Disk Utility won't allow me to delete and resize partitions

I'm running OS X 10.9, and I had a linux partition when I updated from 10.8. Since I updated I can't boot on linux, which is no big deal for me. However, I would like to delete the partition that is ...
0
votes
1answer
39 views

Backing up a RAID experiencing I/O issues

I recently began working for a company that has an OS X Server with a PROMISE Pegasus Thunderbolt RAID (RAID 5) attached as a file server. Within my first couple of days, it became apparent that users ...
0
votes
1answer
59 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 ...
0
votes
1answer
21 views

How to rename disk indentifier?

I created 5 partitions on my portable-drive via DiskUtility. $ diskutil list disk2 /dev/disk2 #: TYPE NAME SIZE IDENTIFIER 0: ...
0
votes
1answer
112 views

Is undoing Yosemite's CoreStorage conversion dangerous?

I tried to make an 8 GB partition on my hard drive so I could make it into a bootable drive, like Recovery HD but without the need to redownload the OS, but for some reason Disk Utility wouldn't let ...
0
votes
1answer
40 views

Remove partition and restore the space without erasing

Time ago I split the hard drive (500gb) in two partitions (250 each), now I don't need them anymore, so I have first erased successfully one partition and now I have still the second one (Mac HD 2) ...
0
votes
1answer
80 views

Flashing folder icon appeared once after changing Macbook hard drive

About 2 weeks ago, I updated my late 2011 Macbook Pro hard drive to a Crucial MX100 solid state drive. The drive installation and data migration went fine with no issues, but today I found the ...
1
vote
1answer
251 views

Why does Disk Utility show one “Macintosh HD” as a logical drive and another that says core storage physical volume

I am trying to figure out why I have 2 Macintosh HD Drives Appearing in disk utility. One of them i can mount and shows it as being a logical drive and the second one i can't mount but it says it has ...
0
votes
2answers
117 views

Is my hard drive already dying?

Although everything is working fine with my Macbook Air from Mid-2013, I have a few errors that bother me. Here they are: Onyx says this: The SMART status was not verified because it is not ...
1
vote
1answer
176 views

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 ...
2
votes
1answer
4k views

Resizing dual boot partitions in Yosemite

I have a dual boot Macbook Air with Yosemite and Ubuntu. I would like more space on my Ubuntu partition and need to therefore reduce the size of the Mac partition. I assume this will cause some damage ...
0
votes
0answers
19 views

Diskutil can't add drive to mirror

bash-3.2# diskutil appleraid add member disk3 disk8 Started RAID operation on disk8 LookingGlass Unmounting disk Repartitioning disk3 so it can be in a RAID set Unmounting disk Can't write the RAID ...
0
votes
1answer
167 views

Trying to boot up on Mavericks USB Install Drive, receive prohibited sign on screen

I have a late 2011 Macbook Pro and I had Mavericks, which ran just fine, but I upgraded to Yosemite after hearing some good reviews. I didn't back it up in time machine. It made my laptop extremely ...
0
votes
1answer
59 views

Replace Recovery HD with a “bootable drive” formatted partition?

A while ago, I had the idea to use the bootable Mac OS X USB drive-making procedure on a hard drive partition, so that I could basically have a version of the “Recovery HD” that doesn’t need to ...
1
vote
1answer
117 views

I can't create a second partition in Mac

When I go to my disk utility, my main hard gives me results like this It's showing capacity 499gb but only remaining 10mb. Now please see the second image What's happening with my Mac?
0
votes
2answers
111 views

After erasing 200 GB I need to repair it using the Recovery HD

I was cleaning my MacBook Pro, erasing all unused files I had on it. After that I decided to erase the free space, so I will have all my files organized and cleaned the "used space". After that I ...
0
votes
0answers
112 views

My Macbook Air doesn't recognize my USB

I've always used my USB on this computer. The only issue i would have is that it wouldn't always appear on screen, but i would just eject it and put it back in and it would all be ok. Today for some ...
1
vote
0answers
75 views

Is there a way to manually repair a CoreStorage volume?

I was playing around with CoreStorage on a test disk and used the undocumented commands cs addDisk and cs removeDisk. The addDisk command worked just fine and was able to expand a logical volume ...
2
votes
1answer
561 views

Is my SATA cable damaged?

Macbook Pro Mid 2012, original SSD. TLDR; Why could I clone my unmountable drive from an external enclosure but not internally? My SSD broke down a few days ago. It was detected, but I was unable to ...
1
vote
4answers
3k views

How to delete partition disk0s4?

A while ago, I dual booted with ubuntu linux and followed a tutorial on youtube to do so, but later I wanted all of my hard drive to be for osx, so I deleted the ubuntu partition, but now I am left ...
0
votes
1answer
58 views

GPT looks valid. Diskutil sees empty disk

External 3 TB disk. Stopped working after a power bump. GPT reports as follows: bash-3.2# gpt show /dev/disk6 start size index contents 0 1 PMBR ...
1
vote
1answer
47 views

Bootcamp Partition Creation Failure

I wanted to install Windows on my 2011 Macbook Air running 10.8. I had approximately 40 GB of a 120 GB hard drive free and I set Bootcamp to create a 20 GB partition for Windows. Halfway through the ...
0
votes
1answer
4k views

External HDD can be seen in Disk Utility but not in Finder

I've been using my external HDD a lot of times before on my Macbook Pro 13" OS X version 10.9.5, but it doesn't seem to appear in my Finder anymore. It can be seen in Disk Utility, though. Can anyone ...
0
votes
1answer
194 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 ...
2
votes
3answers
5k views

partition map check failed because no slices were found

I own an early 2011 MacBook Pro running Mac OS X Mavericks. Recently, I tried to make 50 GB partition using Disk Utility but the whole process didn't complete, and I had to restart the system as it ...
0
votes
1answer
55 views

Mac Encrypted HDD Please help!

Hi everyone I have encrypted a partition of an external hard drive from the mac desktop. I pressed that key button then pressed memorable and it changed my entire password unknowingly. I need help. ...
1
vote
1answer
87 views

Flashing question mark, low hard drive space

When I booted my Mac last night I got a flashing folder against a gray background. The computer started fine this morning, but when I closed the lid and opened it up again I had to reboot, and now ...
8
votes
3answers
939 views

How much data has been written to my SSD over its lifetime?

Is there a Terminal command which will show me how many GB has been written to my SSD through the whole lifetime of the disk? I'm asking because I want to find out how many cycles have been done. SSD ...
1
vote
1answer
189 views

Remove Bootcamp when Boot Camp Assist will not

I purchased an iMac from a buddy and recently upgraded to Yosemite so I am learning as I go about Macs. However, I decided I wanted it to be quicker so I purchased an OWC SSD to install as a primary ...
3
votes
1answer
153 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: ...
0
votes
1answer
158 views

Macintosh HD disappeared from finder after “disk damaged and cannot be repaired”

I have a MacPro 13.3 Inch mid2011 with 500GB storage and recently while performing a Mac update, it froze and was still stuck on a grey screen even after multiple restart attempts. I finally tried ...
2
votes
1answer
4k views

How to reformat/install new SSD on MBP late2010 using OS X Internet Recovery

I had been saving some money to buy an SSD and finally I did. My old HDDs motor shut down so I had to replace it. I put it in the macbook all good but it isnt recognized by the system as a hard drive ...
0
votes
1answer
317 views

Equivalents for genisoimage and qemu-img on Ubuntu

How do I achieve the same result on OS X 10.9 as I do on Ubuntu with commands: $ genisoimage -output init.iso -volid cidata -joliet -rock user-data meta-data and $ qemu-img convert -O raw disk.img ...
3
votes
2answers
1k views

Erasing partition doesn't give me free diskspace

I'm using a Macbook Air and until today I had two partitions on it (not counting the restore partition). I had my OSX partition and an Ubuntu partition. As I don't use Ubuntu anymore, I decided to ...
2
votes
5answers
7k views

Disk Utility hangs prior to resizing partition

When trying to shrink the size of a partition, the period before the actual resizing happens (where Disk Utility says "Preparing to partition disk") hangs forever. I dug into Console to see what was ...
0
votes
2answers
53 views

Created a second OS X partition, erased the first, now can't delete old partition

I bought a secondhand macbook pro (early 2011). It was running Yosemite, but I wanted to do a fresh install, as initially I didn't have the password. I created a 2nd partition and installed a clean ...
3
votes
3answers
26k views

OS X Yosemite installation error: File system verify or repair failed

My Mac has been running fine until I decided to upgrade to OS X 10.10, Yosemite. When it is installing I get the message: File system verify or repair failed. I clicked the restart option to ...
2
votes
3answers
10k views

Changing a Volume's “Device / Media Name”

I know a Mac volume can be renamed... obviously. But if you look at the output of diskutil you will see that a volume also has a "device name" that corresponds to the name it was given when it was ...
0
votes
0answers
346 views

Resizing and moving OSX partitions in Disk Utility

So, I have a Mac Mini with a 160GB drive (it's an old model but it's only for testing). It had 4 versions of OSX on it but one needed more space so I removed the oldest version (Lion) and want to keep ...
0
votes
1answer
1k views

diskutil eraseDisk results in Error: 12: POSIX reports: Cannot allocate memory

I'm trying to format my usb drive that is partitioned with FAT32 by the following command in Terminal: $ diskutil eraseDisk JHFS+ UntitledUFS disk1 However, I get this output: Started erase on ...
3
votes
4answers
2k views

Why does RAID 1 “Mirroring not provide performance improvements”?

I have always used Software RAIDs, either Apple-provided, or via SoftRAID, etc. I am about to re-zhuzh my arrays and decided to do a little research beforehand… and On Apple's site, there is a ...
0
votes
2answers
50 views

Resizing Partitions

I cannot resize the HD of a new Mac Mini. The Mac HD shows 700+ GB on one partition with Yosemite on it and another partition of 200+ GB named "Free Space" and I cannot figure out how it got there. ...
1
vote
2answers
333 views

Orphaned inodes in SSD in MacBook Pro Early 2011

I have a Macbook Pro 15″ Early 2011. Last year I changed the disk to put a new Samsung SSD (Evo). Recently my computer was really slow. I rebooted on the recovery partition, and tested my disk with ...
0
votes
1answer
85 views

I'm not able to re-size a HD Partition to utilize all its free space, how can I fix this?

I've seen a couple of questions on the exchange that are similar to the issues I am having. But I haven't been able to get things to work referencing those issues. I am ultimately looking to install ...