Ygtjki

Using Mac OS 1.9.5.

I am using brand new external HDD, 4Tb, format with exFAT.
I want to use it to make a backup.

First attempt failed: I thought because I copied large folders at same time.

I formatted the disk, this time specifying cluster block size (4096byte) as suggested for exFAT format in disk of 4TB.

I copied folders, archived, unzipped on the HDD.

No errors.

At the end of the process, I could not eject disk.

I looked if there were pending processes, not one but the one to search for them:

ps aux | grep disk1
gg4u 917 0.0 0.0 2432784 628 s001 S+ 9:19AM 0:00.00 grep disk1

Instead of forcing unmouting, I simply turn off the laptop: no error.

This morning I turn on the machine, OS start by default a file system check, granting yes:

ps aux | grep disk1
root 267 3.6 0.3 2658868 52812 ?? U 8:39AM 0:02.90 /System/Library/Filesystems/exfat.fs/Contents/Resources/./fsck_exfat -y /dev/rdisk1s2

At the end, it launches the error:

OS X can’t repair the disk

It says now file system is dirty (how is that possible, since there was no error while copying and unpacking files)

sudo fsck_exfat -q /dev/disk1s2

QUICKCHECK ONLY; FILESYSTEM DIRTY

I tried a second time, verbose mode:

diskutil unMountdisk force /dev/disk1
Forced unmount of all volumes on disk1 was successful

sudo fsck_exfat -ygd /dev/disk1s2

(S,"Checking volume.",0)
(S,"Checking main boot region.",0)
7813556224 total sectors; 512 bytes per sector
FAT starts at sector 32768; size 7634944 sectors
975736064 clusters starting at sector 7667712; 4096 bytes per cluster
Root directory starts at cluster 29782
Read offset = 0x00000101d000 length = 0x001000
(S,"Checking system files.",0)
Read offset = 0x0000f1454000 length = 0x001000
(S,"Volume name is %1$@.",1)
....
--- [1] Evicted 1 buffers (4096 bytes; 1 pages)
Read offset = 0x0000ebf07000 length = 0x001000
Checking bitmap cluster 7946
Assertion failed: (result->data == NULL), function fsck_exfat_cache_recycle, file /SourceCache/exfat/exfat-66/fsck/fsck_exfat_cache.c, line 248.

Questions:

• 
  Can apple unix properly handle exFAT formatted HDD (no SSD) ?


• 
  Or should I deduce my external drive is faulty (WD Elements 4TB) ?

If HDD is ok, instead is Apple having issues to handled other file systems than its own:

• How to prevent apple checking the HDD file system each time I plug the disk, how to ensure file system will not result corrupted so to normally eject the disk, once done ?

About messages about from fsck:
- Is the exit code 1 for (S,"Volume name is %1$@.",1) an error ?
- What does it mean and how to handle assertion failed error Assertion failed: (result->data == NULL), function fsck_exfat_cache_recycle, file /SourceCache/exfat/exfat-66/fsck/fsck_exfat_cache.c, line 248. ?