

$ diskutil info disk2s1 | grep "Block Size" MacOS: $ diskutil info disk2 | grep "Block Size" I don't have the faintest idea where to start on this issue – what could be the problem here?


NB: (I tried following these instructions for FUSE for macOS, but I suppose they're not really relevant since exFAT should be supported natively in macOS these days.) Mount: disk2s2: unknown special file or file system. The drive also shows up in diskutil as disk2s2 but I can't mount it: /dev/disk2 (external, physical):Ģ: Microsoft Basic Data WD My Book 8.0 TB disk2s2 The drive mainly contains a Synology HyperBackup file (.hbk) which makes up almost single-handedly all of those 4.2 TB.Īccording to Synology DiskStation, the main partition is exFAT and I think the EFI partition is vfat: As can be seen in the screenshot below, usage is around 4.2/8 TB. I have run "First Aid" with no errors.ĭisk Utility incorrectly thinks that the usage is 8/8 TB. The drive shows up in Disk Utility, but mounting does nothing. I am able to mount and read the drive when I connect it to the NAS, but not on macOS Sierra 10.12.6. I can't recall exactly how it was formatted, but I believe it was done with Synology's DiskStation for my Synology NAS.

The method I’m showing here requires some familiarity with the Terminal application, which can be found in /Applications/Utilities.I have a Western Digital MyBook (25EE) 8TB External Drive. You can’t just use Disk Utility to reformat an APFS disk to HFS+ - once it has been converted to APFS, the only options that appear for erasing an APFS disk are to reformat in APFS. In this tech tip, I’ll show you how to revert back to HFS+. What if you accidentally format a drive in the APFS format and then realize you can’t use Time Machine or FileVault 2? I recently ran into this dilemma when I formatted an external drive in the APFS format and it was unusable by Time Machine. For example, APFS is incompatible with Apple’s Time Machine backup application and FileVault 2 (which is used to encrypt full drives), and cannot be used to format Fusion drives - those drives that use a combination of a solid-state drive and conventional hard disk drive. However, there are still some instances where HFS+ needs to be used. Check out this new article to see how to revert an APFS drive to HFS+ easily.Īpple’s new APFS (Apple File System) format is the default format for storage under macOS 10.14 Mojave, replacing the dependable and long-lived HFS+ format. Changes to macOS and Disk Utility in macOS 10.15 Catalina now make this older method obsolete.
