Time Machine fails to back up - perpetually "Preparing Backup"

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Level 1

21 points

Time Machine fails to back up - perpetually "Preparing Backup"

Big Sur 11.4

Time Machine stopped making backups in April, (took me a while to notice)

since then I have only managed to get two or three backups.

I have two backup drives, 8TB each, both seem to be in good working order, one is an enterprise IronWolf Pro which should be super reliable.

plenty of disk space on both the system drive and the backup drives.

booted into recovery, and performed disk first aid multiple times on all three drives, no issues were found and did not help TimeMachine.

Apple support suggested that I rename the backup folder, and one backup was done to a new folder, but no more.

after that one backup was done, I felt safe enough to re-format the older drive (Time Machine formatted it as APFS) and managed to get one backup done.

but that was it.

now Time Machine is again "Preparing Backup" for days and even weeks... (I attempt to minimize restarting the machine while it is "preparing backup"), I keep the Time Machine Prefs open on the desktop so I can see what it is doing (or not doing)

btw, I re-installed 11.4 from a bootable USB drive twice, just in case... no go

Posted on Jul 15, 2021 11:03 PM

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Answer 1

aviram Author

Level 1

21 points

Jul 20, 2021 8:45 AM in response to aviram

I believe that I figured out why Time Machine is having problems

But I still need help fixing it

Last night I found this wonderful article on this website which has lots of other good content, articles and utilities:

https://eclecticlight.co/2020/07/27/time-machine-17-using-utilities-to-solve-problems/

downloaded T2M2 and saw that Time Machine was backing up about 5000 files, but… it said something like 100,000 of 5600 or so files!

Which T2M2 said it took over 11 hours to “prepare”

all of which were in a folder called .cleverfiles

apparently I had installed Disk Drill years ago and forgot about it

I did notice that cfbackd was crashing multiple times per day but at the time I did not associate it with cleverfiles disk drill

so I attempted to remove it.

Disk Drill crashed while removing its data files

then I looked at the .cleverfiles folder, it has a sub folder

hlink.ref

which has over 65000 inodes and size of the directory file itself is nearly 800,000,000 bytes!!!

so naturally I did ls -la

no results

had to kill ls

So I booted into recovery mode, disk first aid did not find anything (as before)

got into terminal

ls -la has been running overnight and even after eight hours no results

so it seems that Time Machine cannot back up this infinitely large cleverfiles directory

which explains the perpetual preparing issue and the fact that it was taking forever to complete a backup.

rm -rivd hlink.ref

came with “examine files in directory hlink.ref” the top level folder and that was it.

It is sitting there for over eight hours just like ls in the other terminal window and did not yet even prompt for the next file or directory to delete…

so my question is: how do I delete it?

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Answer 2

Old Toad

Level 10

215,370 points

Jul 20, 2021 9:49 AM in response to aviram

I experienced the same forever "preparing for backup". I had a rotational HD that was connected directly to the iMac via USB. After a lot of experimentation and tries the following is what I had to do to get TM to reliably backup, quickly and efficiently every time:

1 - boot into the Recovery volume (boot with the Command + R keys held down), launch Disk Utility and run First Aid on the Macintosh HD - Data volume. If you get any error message repeat until there's no errors detected.

2 - reboot normally.

3 - erase the hard drive for Time Machine.

4 - launch TM and select the newly formatted drive to use.

I haven't had any problems since.

Note: I don't have any files on the Time Machine backups that I didn't have on my boot drive or other drives that were being backed up so had no qualms about erasing the TM drive.

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Answer 3

Old Toad

Level 10

215,370 points

Jul 20, 2021 10:21 AM in response to aviram

Have you tried booting into Safe Mode and deleting the files from there?

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Answer 4

aviram Author

Level 1

21 points

Jul 19, 2021 11:42 AM in response to aviram

so go figure this, I had a burst of backups, and then it stopped again, currently "preparing backup" for the last 8 or so hours...

% tmutil listbackups -m

/Volumes/Ironwolf 8TB/Backups.backupdb/iMac/2021-05-18-175254

/Volumes/Ironwolf 8TB/Backups.backupdb/iMac/2021-07-16-030404

/Volumes/Ironwolf 8TB/Backups.backupdb/iMac/2021-07-16-143017

/Volumes/Ironwolf 8TB/Backups.backupdb/iMac/2021-07-16-154149

/Volumes/Ironwolf 8TB/Backups.backupdb/iMac/2021-07-16-173423

/Volumes/Ironwolf 8TB/Backups.backupdb/iMac/2021-07-16-193442

/Volumes/Ironwolf 8TB/Backups.backupdb/iMac/2021-07-16-213412

/Volumes/Ironwolf 8TB/Backups.backupdb/iMac/2021-07-16-233429

/Volumes/Ironwolf 8TB/Backups.backupdb/iMac/2021-07-17-013536

/Volumes/Ironwolf 8TB/Backups.backupdb/iMac/2021-07-17-033513

/Volumes/Ironwolf 8TB/Backups.backupdb/iMac/2021-07-17-053558

/Volumes/Ironwolf 8TB/Backups.backupdb/iMac/2021-07-17-073533

/Volumes/Ironwolf 8TB/Backups.backupdb/iMac/2021-07-17-093630

/Volumes/Ironwolf 8TB/Backups.backupdb/iMac/2021-07-17-112949

/Volumes/Ironwolf 8TB/Backups.backupdb/iMac/2021-07-17-134119

% tmutil listbackups -m -d /Volumes/TimeMachine\ 8TB

/Volumes/.timemachine/E810F4F2-9D78-4329-A334-EE72291F4622/2021-06-25-150425.backup/2021-06-25-150425.backup

/Volumes/.timemachine/E810F4F2-9D78-4329-A334-EE72291F4622/2021-07-16-014218.backup/2021-07-16-014218.backup

/Volumes/.timemachine/E810F4F2-9D78-4329-A334-EE72291F4622/2021-07-16-203406.backup/2021-07-16-203406.backup

/Volumes/.timemachine/E810F4F2-9D78-4329-A334-EE72291F4622/2021-07-16-223425.backup/2021-07-16-223425.backup

/Volumes/.timemachine/E810F4F2-9D78-4329-A334-EE72291F4622/2021-07-17-003533.backup/2021-07-17-003533.backup

/Volumes/.timemachine/E810F4F2-9D78-4329-A334-EE72291F4622/2021-07-17-023542.backup/2021-07-17-023542.backup

/Volumes/.timemachine/E810F4F2-9D78-4329-A334-EE72291F4622/2021-07-17-043546.backup/2021-07-17-043546.backup

/Volumes/.timemachine/E810F4F2-9D78-4329-A334-EE72291F4622/2021-07-17-063540.backup/2021-07-17-063540.backup

/Volumes/.timemachine/E810F4F2-9D78-4329-A334-EE72291F4622/2021-07-17-083546.backup/2021-07-17-083546.backup

/Volumes/.timemachine/E810F4F2-9D78-4329-A334-EE72291F4622/2021-07-17-104233.backup/2021-07-17-104233.backup

/Volumes/.timemachine/E810F4F2-9D78-4329-A334-EE72291F4622/2021-07-17-124818.backup/2021-07-17-124818.backup

/Volumes/.timemachine/E810F4F2-9D78-4329-A334-EE72291F4622/2021-07-18-172340.backup/2021-07-18-172340.backup

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Answer 5

aviram Author

Level 1

21 points

Jul 19, 2021 10:32 PM in response to aviram

and this evening, it started backing up, yet it is now at "1.12 GB of 1.16 GB - About 3 minutes remaining" for the last three hours or so...

this is so weird, why does it take it extremely long to both "prepare back up" and to actually back up?

As a test, I just copied 12GB worth of pictures onto the external disk and the copying finished in about two minutes, yet Time Machine still has not progressed...

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