Apple fsck.hfs borks on corrupted journal

Question

Got message, "Unrecognized disk" and a choice of eject, initialize, or ignore

I chose ignore, then used "repair disk"

Made no difference.

Can this be fixed without reinitializing?

Answer 1

This answer is incomplete. The drive unrecognized has hit me several times after a power outage. This time I was successful at restoring full functionality to the file system.

I will augment this answer in response to comments, or future experiences.

Using DMDE (free version) I found that the partition table had a bad entry. I was unable to figure out how to fix this from DMDE, but was able to fix it from TestDisk.

Reran Repair Disk in Disk Utility. This was not successful.

Tried running it from diskutil (The commandline version of Disk Utility) was not successful.

Used hfs.util to remove the journal.

Two more passes with fsck_hfs cleared the fussing about corrupted journal. Interesting note: The last pass fsck started talking about corrupted journal, even though hfs.util had successfully removed journal, but when finished, reran itself without the notice.

So initially there was some remnant of journal data that triggered fsck thinking it was still journaled.

Once it was cleared, the drive mounted without a problem. I re-enabled journalling, and it's been running flawlessly as my Time Machine backup ever since.

Links:

DMDE: https://dmde.com/

Note that the free version has full partion management capability. Even reading the manual I do not yet understand how to fix a partition entry other than by deleting and recreating.

TestDisk: https://www.cgsecurity.org/wiki/TestDisk_Download

This is more general partition utility. It is a terminal app, running in character mode and is a bit quirky in the way commands work.

It seemed to read the partition table fine, so I wrote it back. At that point my "disk unrecognized" became a greyed out version of my disk name. Progress.