I have a 1TB external hard drive. It was used as backup disk for Time Machine. But from one day, my Mac cannot recognise it.
The problem may caused by my removing disk without ejecting it first.
I can see the disk by
$diskutil list .... This is it. /dev/disk2 (external, physical): #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme *1.0 TB disk2 1: EFI EFI 209.7 MB disk2s1 2: Apple_HFS Chang 999.9 GB disk2s2 $diskutil eject disk2 Volume timed out while waiting to eject $diskutil unmount /dev/disk2 disk2 was already unmounted or it has a partitioning scheme so use "diskutil unmountDisk" instead $diskutil unmountDisk /dev/disk2 Unmount of disk2 failed: at least one volume could not be unmounted $diskutil mount /dev/disk2 Volume on disk2 timed out waiting to mount $diskutil mountDisk /dev/disk2 One or more volume(s) failed to mount
And the results:
$diskutil verifyDisk disk2 Started partition map verification on disk2 Checking prerequisites Checking the partition list Checking the partition map size Checking for an EFI system partition Checking the EFI system partition's size Checking the EFI system partition's file system Checking the EFI system partition's folder content Checking all HFS data partition loader spaces Checking booter partitions Checking Core Storage Physical Volume partitions The partition map appears to be OK Finished partition map verification on disk2 $diskutil verifyVolume disk2s2 Started file system verification on disk2s2 Chang Verifying file system Checking Journaled HFS Plus volume Detected a case-sensitive volume Checking extents overflow file Checking catalog file Checking multi-linked files Checking catalog hierarchy Checking extended attributes file Checking multi-linked directories Invalid parent for directory inode (id = 6286950) (It should be 19 instead of 18) Invalid name for directory inode (id = 6286950) (It should be dir_6286950 instead of temp6286950) Incorrect number of directory hard links The volume Chang could not be verified completely File system check exit code is 8 Error: -69845: File system verify or repair failed Underlying error: 8: Exec format error