73
votes
External drive does not mount after plug off without eject
SOLVED. Had this problem today. OLD external drive, had its own power source, plugged into a surge protector. I hit the power button on the surge protector when I was unplugging something else, and ...
- 731
66
votes
External drive does not mount after plug off without eject
I'd recommend checking if fsck is holding your disk hostage upon connection. This was it for me.
Running ps aux | grep fsck revealed:
root 2587 7.3 0.1 4363584 21780 ?? U 10:...
- 1,836
17
votes
How do I get detailed SMART disk information on OS X (Mavericks or later)
Extending on Lee Joramo's excellent answer you can install the GSmartControl GUI on top of smartmontools. It comes in a Homebrew tap.
So the procedure is:
brew install smartmontools
brew install ...
- 7,464
16
votes
Accepted
Difference between "diskutil unmount" and "diskutil unmountDisk"?
From man diskutil:
unmount | umount [force] device
Unmount a single volume. Force will force-unmount the volume (less kind to any open
files; see also umount (8)).
unmountDisk | ...
- 94.5k
14
votes
Accepted
macOS partition startup Volume type FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF
The proper GUID of APFS partitions is 7C3457EF-0000-11AA-AA11-00306543ECAC.
The default pMBR was replaced with an old-style MBR, probably by the Linux installation!
Your boot system (in Internet ...
- 65.4k
14
votes
Accepted
dd on Catalina gives "Permission denied" error even after grant it Full Disk Access in Security and Privacy
My bad.
If this happens to you, you might want to check the switch on your SD card to see if it is set to read-only. :)
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11
votes
Accepted
How to fix Mac hard drive partition showing as FDisk_partition_scheme
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 ...
- 65.4k
11
votes
Accepted
How to create a read-only RAM disk on macOS from the command line?
Get the device number of the RAM disk: diskutil list (e.g. disk3)
Add some content to the RAM disk 😉.
Unmount the volume: diskutil umount disk3
Mount the RAM disk read-only: diskutil mount readOnly /...
- 65.4k
9
votes
Accepted
How can I create a bootable drive for ArchLInux on macOS?
There is no command in macOS to format a partition to use a linux file system. In other words, there is no equivalent for the Arch Linux mkfs.ext4 command. There are many possible solutions to this ...
- 36.7k
8
votes
Difference between "diskutil unmount" and "diskutil unmountDisk"?
You are using the command incorrectly. When issuing diskutil unmount, you should refer to a partition. You are referring to an entire disk. For example disk0 refers to the entire disk, where as, ...
- 36.7k
8
votes
Accepted
All of a sudden can't open .dmg files on Monterey
I fixed it! - I recently ran a command to stop receiving annoying messages about umounted drives:
sudo defaults write /Library/Preferences/SystemConfiguration/com.apple.DiskArbitration....
- 237
7
votes
Accepted
How to make remove free space and make APFS container take it up
This answer was tested using Big Sur (macOS 11.0.1). For Catalina, set this question.
Boot to Big Sur.
Close all applications. Open the Terminal application.
You can create a new APFS container. ...
- 36.7k
6
votes
External drive does not mount after plug off without eject
If you can see it in diskutil list, locate its identifier (comes in the form of /dev/diskx) and run:
diskutil mountDisk /dev/diskx
while replacing /dev/diskx with your disk identifier.
If even that ...
- 3,659
5
votes
How do I get detailed SMART disk information on OS X (Mavericks or later)
Quite new and compatible with MacOS Sierra, Yosemite and El Capitan option:
Get native precompiled package from
https://sourceforge.net/projects/smartmontools/
Install it, open Terminal and run:
...
- 912
5
votes
Accepted
Format external HFS disk without ESP
You can repartition the disk with gpt and format the partition with newfs_hfs:
Open Terminal.app and to get an overview enter:
diskutil list
Get the partition table of the disk in question (below I ...
- 65.4k
5
votes
Accepted
diskutil info disk0 shows --> Volume Name: Not applicable (no file system)
Your findings are completely normal for a physical disk like an Apple SSD.
A common physical disk partitioned in macOS doesn't contain (a) file system(s) but a partition table, partitions and some ...
- 65.4k
5
votes
Accepted
I accidentally caused one of my encrypted drives to start converting into a decrypted drive. How can I stop it?
Even though it is an external drive, the encryption system being used is still FileVault.
There's currently no method to cancel a decryption of the drive. You'll have to wait until the drive is fully ...
- 73.4k
5
votes
Accepted
How to know what the different `roles` do in `diskutil apfs` shell command
The roles are:
B=Preboot (boot loader)
R=Recovery
V=VM (swap space)
I=Installer (temporary usage)
T=Backup (Time Machine)
S=System
D=Data
U=User
N=Baseband
E=Update
X=XART (hardware security)
H=...
- 73.4k
4
votes
Difference between "diskutil mount" and "sudo mount"
mount() is actually a system call, that means it's a C function offered by the system library (libSystem) to tell the system to mount a disk drive. It will talk to the operating system kernel and ...
- 831
3
votes
External drive does not mount after plug off without eject
That has happened to me many times. Go to Launch Pad, Disk Utility, and select the disk that won't mount. Then select Repair.
- 394
3
votes
How do I get detailed SMART disk information on OS X (Mavericks or later)
Some additional information running smartctl 7.1 on macOS 10.15 (Catalina)+
Behaviour / output varies if SSD types are different, e.g. NVMe vs SATA/SATA Express
NVMe
MacBookPro14,3 (NVMe) 512GB ...
- 201
3
votes
Couldn't open device
Restore a DMG (maybe an OSX InstallESD.dmg or any other application) to the disk/drive via Disk Util. This will overwrite it (deleting all data). Then you can partition again how you like.
I have ...
- 131
3
votes
Accepted
Creating a partition in unallocated space
The empty space is on disk2 right behind your FAT32 partition (index number 4) with the start block 1563172864 and the size 390352270 blocks (visible in your sudo gpt -r show disk2 output right at the ...
- 65.4k
3
votes
Can´t mount encrypted external hdd after encryption was interrupted
A reboot usually un-pauses conversion, so I would try that first. Consider storing the passphrase in your keychain (even if temporarily) so that it mounts when you log in and gets going on conversion ...
- 229k
3
votes
How to reclaim free space partition on macOS High Sierra?
To convert an APFS container to free space you'd have to delete the container first:
diskutil ap deleteContainer disk1
Then you can demote the partition to unallocated disk space with:
diskutil ...
- 65.4k
3
votes
How do I create an encrypted APFS volume from the command-line?
It seems that the volume was created correctly, but hdiutil attach just provides misleading output when you try to mount a disk with an encrypted volume on it. If you use -nomount and then proceed ...
- 418
3
votes
Accepted
How to resize Apple partition?
Disk Utility for macOS Sierra: Partition a physical disk using Disk Utility
Please make sure to preform a backup prior to partitioning. Although a standard process, there's always an increased risk ...
- 9,789
3
votes
External disk does not show in "diskutil list" after premature eject, what can I do?
Reading the man page of diskutil, I found a command that I thought might provide at least some diagnostics on what was wrong:
diskutil activity
When you run this command, it will start monitoring ...
- 161
3
votes
Accepted
MacOS: two hard drives, one empty
It looks like your Fusion Drive got split. Apple has some instructions here explaining how to fix it. I have copied the instructions here, but they made be easier to read and more up to date at the ...
- 2,842
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