SparseBundle stopped working

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Level 1

12 points

SparseBundle stopped working

Even though I am not a time machine user, I have been using sparse bundle images ever since Apple introduced them about 15 years go.

A couple of days ago I tried to mount the volume containing my photo libraries from 2020 to the present. I got an unhelpful error message saying the disk image could not be opened.

So I first tried to verify the file, only to get an equally unhelpful message...

I searched the Apple Community and elsewhere. All references I could find were with regards to Time Machine sparse bundles. Since a bundle is a bundle (unless its plist tells the mac it's a time machine bundle), I tried the advice that appears in every page I visited regarding sparse bundle trouble.

Switched to root and got the disk ID.

Proceeded to run tail -f /var/log/fsck_hfs.log

Instead of "volume repaired successfully" or "volume could not be repaired" I got a "cannot allocate memory" response.

Despite the error above, tried "fsck_hfs -drfy"

Got messages about blocks not being MDB or volume headers. Also unknown volume type.

As per the various online suggestions, the next thing to try was "fsck_hfs -p" before trying "fsck_hfs -drfy" again. Only to get the same errors as before...

Somewhere in the Apple Community discussions there was a suggestion to try "diskutil repairVolume" if "fsck_hfs" does not help...

I have no idea what the errors above mean. The google stuff I look up was not helpful.

As I am lost beyond the outer edges of the known universe, I hope one of the experts here can lend a helping hand.

MacBook Pro 14″, macOS 14.5

Posted on Jun 7, 2024 7:34 AM

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Answer 1

Top-ranking reply

HWTech

Level 9

68,642 points

Jun 7, 2024 5:49 PM in response to Siatonto

I'm not sure why you are running an HFS+ fsck scan on "disk7s2" which appears it may be an APFS volume.

You can try using data recovery software to see if it can access the volume from the "attached" .sparsebundle. Some of those apps may not like working on a .sparsebundle, but some of them should be able to work if you need to attempt data recovery if you don't have a backup of that data.

Did you try using "diskutil" to manually mount the volume in read-only mode after you used the "attach" command? I'm doubtful it will mount even in read-only mode. I've never been able to do so with any APFS volume that has been part of an encrypted volume. Unfortunately there are currently no third party utilities available to attempt repairs on an APFS volume so that is not an option at this time.

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Answer 2

Siatonto Author

Level 1

12 points

Jun 7, 2024 8:19 PM in response to HWTech

Thank you for noticing I was running HFS+ fsck. Having put my absentmindedness aside, running fsck_apfs produced multiple errors:

"verification/reading of the omap object failed: illegal by sequence" errors, "zeroed-out block"
"no valid checkpoint"
"most recent checkpoint is invalid"

Running "diskutil" to manually mount the volume only brings a volume labeled "EFI" that is empty.

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Answer 3

etresoft

Level 9

56,326 points

Jun 7, 2024 8:30 AM in response to Siatonto

I just just talking about this problem in another thread. Specifically, I was talking about people who try something from 2006 and just get deeper and deeper into a rabbit hole before they come here for help.

Don't use sparse bundles. They aren't reliable. Hopefully you have this data backed up elsewhere.

Regardless, take this opportunity to save any remaining data that might still be on a sparse bundle.

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Answer 4

Jun 7, 2024 9:30 AM in response to Siatonto

I'm no expert on sparse bundles; do not use them. This is an article about sparse bundles 12-4-2023 by Howard Oakley.

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