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Mojave time machine back up failing

Since installing 10.14 have not been able to complete a full backup using time machine to external drive. All disks check out on disk utility first aid both under OS and stand alone utility under recovery. Have erased and reformatted the external drive. Still no success. Backup begins and runs up to about 80GB ok, then fails. Restart by "back up now" continues for about 500MB and then fails again. My full backup is about 900GB so I am running unprotected.

I believe this is a Mojave problem, not a drive problem.

Any ideas?

Mac mini, macOS Mojave (10.14), Samsung display

Posted on Sep 30, 2018 12:07 AM

Reply
330 replies

Oct 5, 2018 9:04 AM in response to blesscurse

BTW - I just ran Etrecheck and my late 2013 MaBook Pro did not indicate any major or minor problems other than a warning about future problems may occur with a couple of 32 bit apps. I didn't expect there to be a problem but one other possibility eliminated for me. My Time Machine is connected to a 1 TB WD drive with two partitions, the smaller one for a few movie downloads. The drive uses GUID and is HFS+, Journaled as it should be. The drive I am using now has been in use for two years without a problem other than making restarts and slower switching to bootcamp more noticeable for the past year. I have an alternate drive that I use to alternate with on a monthly basis. I do that for hardware redundancy and it now offers me the option to restore my previous High Sierra in a simple and reliable manner as Time machine no longer works with Mojave. I will simply reformat the drive with the former APFS I have been using and than restore with my month old Time Machine. Any month old files in Document, Photos or Music that are lost can be restored from my Google drive and any app updates will come from Apple or my other sources. I doubt there is more than one or two.


Time Machine worked well on my 2011 Mac Mini over a year ago when I installed a 500 GB SSD. I was very impressed with Time Machine as it was a perfect restore and effortless with the exception of the few hours needed for the actual restore. I didn't have to nurse anything along or migrate a **** thing.

Oct 5, 2018 10:29 AM in response to georosejr

Same too me, i have three drives, all working correct for years, after the mojave update all are failing, i formatted one of them new, but the backup fails after a while.

In the console i have a lot of violations in the sandbox of about 100 files.

The question about the apple responsibility is attached because so many users spend their time, in my world this is called betatesting and it costs the company money.

I will test the idea of the case senstive formatting and give a feedback here.

But then the important question is, why only a few users and not all, cause case sensitive is rare i think.

Oct 5, 2018 11:33 AM in response to sepsus

Even if the case sensitive formatting allows the Time Machine backup to work, it would not be a fix, it would simply be masking an underlying problem because Time Machine is designed to work with both case sensitive and case insensitive HFS+ Journaled formatted drives, as it has for many years. I'm very anxious if anyone else sees the same behavior I have, which is Time Machine backup working 2 out of 2 times with case sensitive HFS+ journaled, case sensitive formatted drives. Since it started working it's been working fine for 2 days making successful incremental backups every hour without any errors. I'm as disappointed as anyone about Time Machine being broken, but having been intimately involved in all facets of software development for more than 30 years these things happen because of the massive complexity of software systems and the fact that no software is ever 100% tested for all possible conditions. Lots of moving parts + built by humans = something is going to break at some point. It's never a question of IF, only a question of WHEN.

Oct 5, 2018 1:52 PM in response to sjordi

I also tried to indexing Spotlight new, and it takes by now about 9 hours and have had about 25%, maybe there is also a problem with, or maybe this is the problem, because TM cannot check exactly what is changed and stops their.

Maybe you will test this also, i have 1,5 TB with 180 GB it should be much faster, ;-)

Oct 5, 2018 3:28 PM in response to namuang26

I absolutely agree with you! It is a problem of the new Mojave operating system; Time Machine has always worked perfectly with macOS High Sierra updated to release 10.13.6.

In my case, the backup starts and runs correctly up to 18.56 GB on a total of about 50 GB. Then Time Machine crashes giving an error message with which it warns that there were problems in copying the files and also informing to try to use the "Disk Utility" for the repair. Even if you restart Time Machine, the backup still continues for a few hundred MB and then crashes again giving the same error message.

Now I am not able to find a possible solution to this "block" of TM.

I hope that "mom" Apple can intervene soon maybe with the release of the first update of Mojave.

Greetings from Italy…

I hope Google has translated my message correctly.

Oct 5, 2018 4:27 PM in response to sjordi

What happens if you don’t give up? The time remaining estimates are adjusted dynamically and can change radically. It would be interesting to know if the process would complete if allowed to run to completion, or failure. FWIW the Apple Time Capsule uses case sensitive format for the integrated disk. Even when I could not get any of my USB3 or Thunderbolt direct connected drives to work with Time Machine the Time Capsule still worked. Oh, SuperDuper! worked fine with the same drives that failed with Time Machine.


If you contact Apple support they will assume the problem is with your external drives. You’ll have to keep pressing them to consider that Time Machine software is possibly at fault. I don’t think they monitor user forums but I copy & pasted this discussion to the chat thread I had with a senior Apple advisor. I have no feelings either way that Apple is even looking at this issue with any level of concern.


I’m pretty obsessed about Time Machine because it has totally saved my bacon on several occasions. Knowing that my safety net is compromised is very disturbing.

Oct 5, 2018 6:16 PM in response to Dr_Macintosh

For more than a week now many of us experiencing this Mohave bug have put in countless hours of our time trying to figure out workarounds and ways to get a proper backup of our data. Thats what we do. But, as has been questioned by me and several others on this thread - where are Apple and why are they not responding or even acknowledging the problem and offering researched assistance? Not good enough support by a long way.

Hopefully this case sensitive format workaround works and permits valid and secure backups for those trying it, but it makes me nervous. I for one will continue using SuperDuper (which definitely works) until Apple release a formal patch release containing a tested and verified fix for this. No more erasing and reformatting drives, trying out lengthy backups in the hope that it might work. Who knows that Apple won't invalidate the case sensitive format option when they eventually fix this? Enough!

Oct 5, 2018 10:07 PM in response to namuang26

Like another said in this thread, the work-around for this appears to be formating your time machine drive to case sensitive format. Once I did this, all my back ups are now successfully completed. obviously this still needs to be addressed, but for now there is a way to back up your data with time machine. I do wish more people would read through the posts instead of inserting so much mindless cannon fodder. But here is to wishing. You know what they say...

Oct 5, 2018 10:15 PM in response to Dr_Macintosh

This does indeed work. Now all they need to do is fix it. but for now it is a great work around.

Thank you!


Now if the whiners would read the posts instead complaining so much. Yes it stinks, but any new version of OS has the potential of major bugs. This bug aside, this has been a very stable release overall. We took the risk of being guinea pigs by impatiently installing a brand new version and yet some of us expect it to be flawless? 😮 psssh.

Mojave time machine back up failing

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