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36

I recently had the same question and found a command line tool www.smartmontools.org which can be installed via brew: brew install smartmontools you can then run it smartctl -a disk0s3 for the full report where disk0s3 is the disks physical backing which can be found in Disk Utility.app by getting info on the drive. (There must be a way to find this ...


34

OK, this isn't too bad. Reboot while holding Command ⌘-S to enter single user mode. When it gives you a prompt, type fsck -fy then press return. it will repair your disk. When it's done, type reboot and try partitioning again.


34

You can use the dd command to make a bit-perfect clone of a drive. It's a command line tool that ships with OS X. In order to make the clone perfect you'll need to ensure the source and the destination aren't actively in use. To prepare for the clone I recommend creating a secondary boot disk that you can boot from. Your source for the clone should be an ...


24

From the DropDMG manual: Sparse bundle disk images appear as a single file but are actually stored as a folder with many files inside. This makes it more efficient to back them up using Time Machine or other backup utilities, as only the changed parts need to be copied. Additionally, sparse bundle disk images work well with the Compact ...


24

The problem appears to happen when you unmount the image using umount. Remount the image (either using hdiutil attach or just double click the image) and use the command hdiutil detach it again. This will unmount and eject the image. hdiutil detach /Volumes/<your image>


24

You can force unmount a drive by running the following Terminal command: diskutil unmountDisk force /Volumes/VOLUMENAME Replace VOLUMENAME with the name of a volume on the disk you are trying to unmount. Following this, attempt to Erase/Partition the drive again in Disk Utility. Using the above command can interrupt file read/writes, which can cause file ...


24

If I understand your question correctly you are trying to resize the volume group or actually one of the volumes within a group. From what I could gather your disk was converted to a CoreStorage Volume. Could you please verify that by issuing the following command in a terminal and check if you get a similar output to the one in the picture: diskutil ...


24

After gaining some experience with CoreStorage volumes, I reworked my first answer to generalize and facilitate it by adding some scenarios and deleting some dispensable steps. Basically there is one undocumented command to resize or expand a CoreStorage volume group and an inherent logical volume: diskutil cs resizeStack LVUUID size The command ...


20

Looks like your MacSSD2 partition has been turned into a Core Storage volume. Core Storage is Apple's underlying system for disk encryption - I assume you enabled encryption when you created the partition? You can show the Core Storage volume group using the command diskutil cs list and then delete it using diskutil cs delete <volumegroup-uuid>, where ...


18

It's simply telling you that the file has been modified, and because it's been modified Disk Utility can't fix the permissions on it. ARDAgent.app is the Apple Remote Desktop agent, and the file shown in the path above is the binary file contained within the app package. It's normal for the file to be shown as an error here. Simply ignore it. Apple KB ...


17

FAT32 (called MS-DOS (FAT) by Disk Utility; a filesystem originally released in 1977 and updated a few times since, lastly in 1996) really is the only cross platform filesystem that is going to work fully out of the box with Windows and Mac OS X. Be careful though, if you are using Disk Utility to format the drive, you should make sure to choose the Master ...


17

The error message is pretty unclear, but one reason might be that you are not connected to the power outlet. Compacting a disk image might be a long and intensive task, and sometimes the OS denies it when you are running on battery to avoid any risk of data loss. If you are positive that you have enough battery power to complete the task, you may overrun ...


16

In terminal, you can use diskutil to get information about the drive, including the device block size: $ diskutil info / | grep "Block Size" Device Block Size: 512 Bytes


14

Most of the difference you're seeing is due to Time Machine's "Local Snapshots" feature. When Time Machine is turned on but the backup device isn't available, it backs up to the local volume. The space used for these local snapshots is counted as "in use" by Disk Utility and System Information, but not the Finder (see the Disk Space considerations section ...


14

There is a chance to repair it with command line (in Terminal) with the terminal utility as described in Apple's support docs, shown below: Use the command line and the fsck_hfs -l command. Start up your computer and log in as an administrator. Open Terminal (/Applications/Utilities). At the prompt, type the following command and then ...


13

If your partition turned into Logical Volume Group (you can't resize or delete Yosemite partition), you can revert partition type with few command line. Open Terminal type diskutil corestorage list Find Yosemite partition UUID string. type diskutil corestorage revert <UUID> Your Yosemite partition is now revert to default partition type. Now, you ...


12

(Before proceeding, please make sure the disk in question is still disk2, you have backups of your data, etc. - that said, the changes here are not particularly dangerous. Read through the whole instructions before doing anything to make sure you understand all the steps.) OK, your partition tables look fine (a valid GPT and a correct protective MBR), so I ...


12

On Snow Leopard, you would need to boot from an external OS to wipe the drive. On Mountain Lion (or Lion), the system makes a recovery HD so you can self-wipe the Mac. This is a much, much faster and easier task, so I recommend you upgrade first and then do the wiping using a recovery boot and Disk Utility. I personally would do these steps (and you could ...


11

Selecting "MS-DOS (FAT)" will automatically format as FAT16 or FAT32 depending on the target's size.


11

The following diskutil cs resizeStack command is vastly undocumented and as such potentially destructive. There might be an easy way outlined first and a long winding, time consuming hard way. Please backup your Mac OS X before proceeding. The not-as-long-as-expected way: A 2nd computer or an iPhone with the stackexchange credentials to enter the site ...


11

Theoretically everything is fine with your Fusion Drive. Fusion Drives look like this. Disk0 is your SSD with 121 GB and disk1 is your HDD with ~1 TB (~1.121 TB summed up). The larger parts of your SSD (disk0s2) and your HDD (disk1s2) are pooled to a CoreStorage LVG (Fusion Drive: disk3) with a size of 967.8 GB. The rest is reserved for EFIs, a Recovery HD ...


10

Using exFAT would be a good idea if the Windows computer runs Vista or Windows 7. This is a “simple“ filesystem yet it supports > 4 Gb files and multi-terabyte partitions. For compatibility with 32 bits filesystems you still have to use MBR, not GPT.


10

If your goal is to completely wipe all data which is on your current boot disk, then follow the procedure below. Insert the Mac OS X CD. Restart the computer. Immediately after the startup sound, press and hold the "C" key to start up from CD. When the Installer screen appears, do not click Continue. Instead, choose Installer > Open Disk Utilities. ...


10

First, note that Device Block Size is different from the block size in use by the filesystem. The former value as reported by diskutil refers to the raw block size used by the hardware. I haven't found an easy way to check the latter value by the command line, but you can just create a zero-byte file then do Get Info from the Finder. It will say 0 bytes, but ...


10

It turns out that Disk Utility didn’t want to touch a disk that contained an encrypted partition, but it had no issue with changing the encrypted partition itself. I clicked on the encrypted partition (not the drive) in the sidebar, and the “Erase” tab appeared on the right. From there I reformatted the disk to Mac OS Extended without encryption, and ...


10

The HDD is formatted using FAT32 which has a known limitation of 4GB file size. You need to format it using exFAT which is supported by OS X and Windows.


9

You can't change where each partition starts (i.e. where the top of it is in the partition diagram), only where it ends. But in your case, since you have a free block as large as the partition you want to change, you can work around it (warning, this is untested under Lion, so make sure you have a good backup first): Create a new volume in the blank space ...


9

FAT32 (called MS-DOS (FAT) in Disk Utility) is a cross compatible file format although you will be limited to 4GB maximum per single file. Plugins for the mac can also allow it to handle using NTFS volumes, which is a more desirable solution


9

You want to run diskutil coreStorage unlockVolume <UUID>, where the UUID is the Logical Volume UUID associated with your encrypted disk, /dev/disk3. You can get the lvUUID by running diskutil cs list in the terminal and looking for the output related to /dev/disk3. The identifier is a long string that would look something like this 'B807C2A0-577F-...


9

I highly recommend completely backing up the machine before attempting this, either using TM with no exclusions set, or better yet, cloning the whole drive using a program like Carbon Copy Cloner. Unmount the Logical Volume: sudo diskutil unmount force /dev/disk1 Remove the Logical Volume Group and all of its contents: sudo diskutil cs deleteLVG ...



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