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19

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 ...


7

OS X includes a command line tool called split. See man split for all the details. You can call split using the Terminal.app and the command: split -b 5000m MYBIGFILE To combine it again, have the receiver store all parts in a dedicated folder, open Terminal there and run cat x?? > MYBIGFILE (This assumes that you used the default output names ...


6

Booted to Internet Recovery Mode you have to remove all non-OS X partitions, modify the partition types and then resize your main volume. The reason why you can't boot your Mac is the bogus partition type (FFFF-FFF....) of your main partition (i=2/sda2). Additionally the Recovery HD partition (i=3/sda3) has the wrong type. Preparation: Restart to Internet ...


6

The method to repair your disk and recover the GUID partition table is related to my answers to similar questions: HFS+ invalid number of allocation blocks and Hard drive no longer accessible. Basically you have to find characteristic strings of JHFS+ volumes, use some simple math and common sense and have some luck to fix the GUID. And don't loose sight of ...


5

You want to run diskutil coreStorage unlockVolume <UUID>, where the UUID is the Disk Identifier associated with your encrypted disk, /dev/disk3. You can get the identifier by running diskutil 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 ...


4

If you format a drive as Encrypted, you are in fact turning on File Vault, as that's the only encryption layer that OS X supports. The main advantage of partitioning the drive as Journaled, and then turning on File Vault is that you can revert the drive to a simple unencrypted volume if you should choose to do so in the future. You can't do this with a ...


4

Read out the following S.M.A.R.T attributes of your SSD with an appropriate tool*: 241 - Total LBAs Written: The total number of 512-byte sectors written during the entire lifetime of the device. 242 - Total LBAs Read: The total number of 512-byte sectors read during the entire lifetime of the device. A second set of attributes is: 174 - ...


4

The original post mentions that SSDs have a 1000-2000 cycle limit, which over-simplifies the problem. Individual cells in an SSD may have such a limit, but the SSD implements many different solutions: from over-provisioning and write-levelling to Sandforce's proprietary collection of de-duplication, compression, and data differencing techniques, which it ...


4

With Apple's OS X tools you can't expand the start sector of a partition to lower sector numbers. You have to choose another method. You may accomplish your objective if less then one half of the net capacity of your hard drive ((~disk size - size of Recovery HD - size of EFI)/2) or less then one half of the main volume is occupied. If you miss the ...


4

You can't create an ISO image from a non-image file. hdiutil and especially hdiutil makehybrid expect an image or a directory (not necessarily containing files!). But you don't have to unzip/unarchive anything. Just create a folder with the name MAKE, move the gz file into it and then enter hdiutil makehybrid -o ~/make.iso ~/MAKE -iso -joliet. The ...


3

hdiutil will show information about all mounted DMGs: hwd@hwds-iMac:~$ hdiutil info framework : 415 driver : 10.11v415 ================================================ image-path : /Users/hwd/Downloads/mountedImageOne.dmg image-alias : /Users/hwd/Downloads/mountedImageOne.dmg shadow-path : <none> icon-path : ...


3

To expand your CoreStorage Logical Volume Macintosh HD you have to delete the blocking NO NAME EFI partition (disk1s5). The two unnamed parts (138.62 GB and 99.9 GB) are no partitions but unallocated disk space. To remove the second EFI partition (and expand Macintosh HD) you have to boot to Internet Recovery Mode or an OS X system on an external device. ...


3

No, just moved them. Method 1: Disk Utility > Menu > File > Unlock (Embarrassingly I found this item after posting the question and using command line option to unlock the drive) Method 2: Command line, open "Terminal" hdiutil attach /dev/diskXsY Where X,Y are system specific numbers like 1,2,3.


3

To get some additional un-allocated disk space on disk0 to create a new partition you have to shrink your CoreStorage Volume Group and all subsequent CoreStorage items. To resize the CoreStorage Volume Group in your case you have to use the Terminal booted to an external boot drive. Preparation: Backup your data. Detach any external drive (especially ...


3

The maximum allocation block (or cluster) count for exFAT is 2^32 = 4,294,967,296. To get the minimal size of an allocation cluster on your partition divide the size of your partition through 2^32. Examples: for a 100 GB partition the minimal size is 100,000,000,000 bytes/4,294,967,296=~23.3 bytes. Since the smallest device block size is 512 bytes, the ...


3

I use Daisy Disk to keep tabs on what's using up space on my disks. Like @Hoshts and @Joonas have mentioned in their comments on another answer it's not free, but gorgeous and easy to understand. Money well spent, in my opinion, unless you're just looking for a one-time solution.


3

You can't simply merge a Bootcamp partition or empty space and a FileVault volume with Disk Utility (Boot Camp Assistant should handle this though). You first have to remove the Bootcamp partition and then expand the FileVault volume. To remove the Bootcamp partition and resize the CoreStorage Volume Group (containing the FileVault volume) the Mac has to be ...


3

Windows' Disk Management has overwritten the GUID partition table with something unknown. This usually only effects the partition table but not the content of your disk (though it seems to be gone)! A proper GUID partition table has to be restored. The particular obstacle here is: the OP neither has a thumb drive nor a second Mac. Preparation: Backup the ...


3

My first thought would be that it is a permissions error of some kind… Either the Drive is formatted as NTFS or ExtFS etc The System doesn't have write permissions to the device itself For the first, the simplest, if not cheapest solution would be something like Paragon NTFS or ExtFS or Tuxera NTFS If it is a pure permissions/ownership issue, then for ...


3

To delete CoreStorage volumes you have to use the CLI: please backup your volume "mainHD" boot to Internet Recovery Mode (hit altcmdR immediately after the start-up chime) open Disk Utility and check/repair mainHD quit Disk Utility , open in the menubar Utilities/Terminal.app and enter diskutil cs deleteVolume LVUUID to delete the Logical Volume in your ...


3

This Ask Different post has what you're looking for. Don't go looking for an "answer," the author for some reason decided to write his own answer in the "question" post. The method worked perfectly (and non-destructively, but you should always take a backup anyway, just in case) for me! Paraphrased: Reboot in Recovery Mode by holding down Command-R ...


3

Short answer: yes, it's because of FileVault (well, actually Core Storage, but that's required for FileVault). It's normal for the startup manager (Option key at startup) to only show one volume in this mode, but Command-R should still work to start in recovery mode. If Command-R is not working, I'm not sure what the problem there is. Long answer: starting ...


3

This is an example of a procedure to erase an external disk containing a single encrypted partition. Open the Disk Utility application and highlight the "Logical Volume Group" representing your external disk. An example is shown below. (Hint: click on image for a better view.) Next, click the Info icon to get the pop up window. Note, in the example shown ...


3

I would suggest the Profile Management option that is included in OS X Server. It has all of the described above features and it is really easy to operate with. Take a look at https://www.apple.com/ca/osx/server/ it's $22.99 CAD.


3

Sorry to hear of your situation. The first megabyte will have included the drive's partition and critical structural information. If you can, dd all the remaining content to another drive as a back-up of sorts. Then I suspect your best choice is a professional repair service or a tool like DiskWarrior: DiskWarrior Everything just disappeared after ...


3

This is likely coming from one or two things (or both). Partitioning a disk, any disk, takes up drive space. In the megabyte range it is not even noticeable. In the gigabyte range it can be a substantial byte (sorry...) out of the drive. Also computer makers and Drive/RAM makers often calculate bytes differently. O/S companies (Apple, Microsoft, etc...) ...


3

How old is the drive? Flash memory has limited write cycles, and it will slowly change into a read-only device. If you have been writing stuff to the drive for a few years it is quite possible some blocks have reached their write limit and the controller has marked them as unusable. Cheaper drive -> fewer cycles. Also note that the one-pass-of-zeros secure ...


3

exFAT is not optimal for your situation probably, but unfortunately there isn't really a no-brainer solution for using an external drive frequently with both OS X and Windows, reading/writing large files, and with really low risk of data loss. exFAT is not a journalled file system, so there is higher probability of data loss than with NTFS or HFS+. exFAT ...


2

Disk Utility will not fix every conceivable disk corruption issue. For that you need third-party apps. I use Diskwarrior and have also had success with Drive Genius. However there is one way to do this without buying a disk repair utility. Back up your hard drive, partition/reformat it, reinstall the OS and restore your backup. Yeah it's more complicated ...


2

From the Tom's Hardware Forum: By default, the OSX disk utility creates a new partition as GUID. Windows can't read it. You need to create the partition type as MBR, which Windows can read. Then format as exFAT and both machines will read it.



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