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8

When using OS X, it's usually more advisable to use diskutil for disk-related activities. TL;DR: To mount a volume/disk by identifier: diskutil mount /dev/diskXsY # mounts just that volume diskutil mountDisk /dev/diskX # mounts the whole disk To mount a volume by UUID: diskutil mount [Volume/Partition UUID] To mount a volume by label: ...


7

I found this worked perfectly (from the terminal): diskutil eraseVolume ExFAT MyName diskX You'll need to change diskX to whatever the number is for your drive. You can find that out in disk utility, select the drive, click info, and look under 'BSD device node'


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

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 ...


6

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.


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

I/O Error usually means your disk has hardware failure. I would backup everything ASAP and change the disk. Disk Warrior will probably not solve the issue as it's only repairing a corrupted filesystem. If you can mount it at some point (try repeatedly), use Carbon Copy Cloner to backup your important data on a new drive. If you can't, try some recovery ...


6

Your drive is in the process of failing and will soon become unusable. Drives fail for a number of reasons and all modern drives will try and protect your data by moving what it can from bad sectors to good ones then mark those sectors bad so nothing gets written to them. However, if the data is corrupted to begin with, moving it only means you are ...


6

It depends on your viewpoint: a file written to an encrypted disk image is immediately written encrypted to the HDD/SSD where the disk image resides. Since the file system of the unlocked disk image is still mounted, the file appears as "unencrypted". So a user, who can access the raw HDD/SSD only, can't read/decode the file content, but a user with the ...


5

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 : /System/...


4

As discussed in fuse-ext2 / OSX 10.11 "El Capitan" make fails, installation of fuse-ext2 fails on OS X 10.11, El Capitan, due to System Integrity Protection (SIP). The recommended solution right now is to disable SIP.


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

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 ...


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 ...


4

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. ...


4

Your main volume is encrypted with FileVault and still locked – consequently it doesn't show up in /Volumes. Before being able to mount it you'd have to unlock it: diskutil cs unlockVolume lvUUID #replace lvUUID by the one shown in the diskutil listing You will then be asked to enter the passphrase/password. You have to enter a passphrase or a password of ...


3

The storage mechanism where each backup is a full backup is what takes so incredibly long to verify a Time Machine drive. The multi-linked directories is precisely why Time Machine makes the check so slow and precisely why each backup doesn't save two copies of the same file. You can benchmark this by timing your Mac and see how long it takes to verify the ...


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

When you don't use the Boot Camp utility to remove Windows, the Windows boot image on your EFI partition is not removed. This is what you see when you hold down ⌥ during boot. The procedure to solve this is not for the faint of heart. You need to mount the EFI partition in OS X (normally, it only gets mounted for system updates). Mounting the EFI partition ...


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. One thing to keep in mind - the Mac App Store version of Daisy Disk is ...


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

Please try the following: Get the disk identifier of your external 3 TB drive diskutil list Below I assume the disk identifier is disk6 unmount the disk: diskutil umountDisk disk6 Overwrite the first 40 blocks: sudo dd if=/dev/zero of=/dev/disk6 bs=512 count=40 Create a new gpt: sudo gpt create /dev/disk6 Check the disk info with: diskutil info /...


3

This is not an answer, but rather an example of how to extract the GPT partition information from the data you presented. The secondary (backup) GPT partition entries were used because you did not post the contents of the primary GPT partition entries. The document "GUID Partition Table" was used to interpret the data. Last usable LBA can be found in the ...


3

Update: IOReg gives the partition UUID, not the volume UUID, as it operates below the HFS layer. I had incorrectly assumed that the device UUID was required rather than the volume UUID because it was substituting for a device node. To get the volume UUID, use hfs.util. For example: /System/Library/Filesystems/hfs.fs/Contents/Resources/hfs.util -k disk0s3 ...


3

After some trial and error, I finally figured out what the problem was and found a solution. Hopefully this will help those who come across this thread with the same problem. The problem: Reformatting using Disk Utility did not create a child partition, but only formatted the whole drive as FAT. In Disk Utility one can derive this from the "Partition" ...


3

To most easily resolve this, you need to erase your USB drive with a "Master Boot Record" scheme. Steps: Open Disk Utility Select the USB drive Click "Erase" Choose Format "MS-DOS (FAT)" MOST IMPORTANT: Choose Scheme "Master Boot Record" Click Erase button Many thanks to nholtappels for figuring out the problem!


3

By accident I tried to install OS X to the OS X Installer DVD iso file (mounted to the virtual VBOX CD-ROM device) itself. Erasing/partitioning the VBOX HARDDISK disk (see images in question) and creating a new HFS+ Journaled formatted volume seems to work.


3

Boot to Recovery Mode (hold cmdR while booting). In the menubar open Utilities -> Terminal. Now change your working directory and go to /Volumes: cd /Volumes List all volumes: ls -l Move to your main volume cd name_of_main_volume Now you can move forward to a directory to remove files and folders with cd folder_name. Appropriate paths to remove ...


3

When you create an image and you select Compressed, you are doing so at the sake of speed and read/write capability To access the data on a compressed image, you have to uncompress it first; that takes cycles (cpu time). Secondly, per Apple, the image is read only, not read/write so you will lose that capability as well. The "Compressed" format is great ...



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