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Does your Big Sur 11.5.2 Time Machine backup drive pass Disk Utility First Aid?


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    16

vett93

macrumors 6502
Original poster
Jul 27, 2014
279
40
California
Can you please run a Disk Utility First Aid check on the Time Machine backup hard drive and respond to the poll if it passes or fails the check? This is for users of Big Sur 11.5.2 and you use spinning disk hard drive(s) for TM backups. Please also indicate the type of Mac you have (e.g., 2013 Mac Pro, 2019 Mac Mini, etc.) Please do not respond if you run a different version of MacOS or you use SSD for backup.

Ever since I updated the MacOS to Big Sur 11.5.2 on my 2013 Mac Pro (Trashcan), I have run into this issue. I have tried 3 HDs and they all failed. They are directly connected to my Mac Pro. The error message looks like below:
Screen Shot 2021-08-25 at 11.22.49 AM.png
 
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jz0309

Contributor
Sep 25, 2018
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I started seeing my external USB HDDs fail after I upgraded from Mojave to Big Sur 11.4 ~ 8 weeks ago. Nothing has changed with 11.5.2...
 

ignatius345

macrumors 604
Aug 20, 2015
7,574
12,923
I got the same result (using MacOS 11.5.2 and a portable spinning HDD), but I'm also not having any problems with Time Machine. Is it possible this is more an issue with Disk Utility?

Are we talking here about the drives actually not working correctly, or just about what Disk Utility is reporting?
 
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vett93

macrumors 6502
Original poster
Jul 27, 2014
279
40
California
I got the same result (using MacOS 11.5.2 and a portable spinning HDD), but I'm also not having any problems with Time Machine. Is it possible this is more an issue with Disk Utility?

Are we talking here about the drives actually not working correctly, or just about what Disk Utility is reporting?
It is possible. I use Disk Utility to check external SSD drives and they all pass though. I don't have Time Machine backup problems most of the time either. But I noticed that TM did fail a few times. When that happened, the MacOS ejected all the USB devices (webcam, microphone, speakers, etc.) that were attached to the Mac.
 

jz0309

Contributor
Sep 25, 2018
11,318
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SoCal
I got the same result (using MacOS 11.5.2 and a portable spinning HDD), but I'm also not having any problems with Time Machine. Is it possible this is more an issue with Disk Utility?

Are we talking here about the drives actually not working correctly, or just about what Disk Utility is reporting?
That is certainly a possibility, but, my 2 HDDs were WD and I downloaded a utility from WD and it showed failures too, just as sporadically as FirstAid, sometimes pass, sometimes fail. I've been running tests for 2-3 weeks and what I have observed:
. TM has failed a couple times.
. Copying files via Finder has always worked
. Backup via CCC has always worked.

So I do believe there is something related to T?M, and since TM reformats a drive to APFS case-sensitive, my suspicion is that it might be APFS on HDD spinners that is involved, but I cannot prove that.
 

ignatius345

macrumors 604
Aug 20, 2015
7,574
12,923
It is possible. I use Disk Utility to check external SSD drives and they all pass though. I don't have Time Machine backup problems most of the time either. But I noticed that TM did fail a few times. When that happened, the MacOS ejected all the USB devices (webcam, microphone, speakers, etc.) that were attached to the Mac.
Are you working with a hub? I wonder if that's got something to do with it. They can be finicky sometimes.

The only thing I keep finding is mysteriously skipped Time Machine backups. I used TimeMachineEditor to tweak the settings so I only do two backups a day and every once in a while it just seems to silently fail.

No other issues with ejected devices, though.
 

vett93

macrumors 6502
Original poster
Jul 27, 2014
279
40
California
Are you working with a hub? I wonder if that's got something to do with it. They can be finicky sometimes.

The only thing I keep finding is mysteriously skipped Time Machine backups. I used TimeMachineEditor to tweak the settings so I only do two backups a day and every once in a while it just seems to silently fail.

No other issues with ejected devices, though.
These HDDs failed on direct connection. My MP has 4 USB ports. I use two of them for TM backup. They fail Disk Utility's First Aid. I was wondering if my MP does not have enough power for them. So I use a powered USB hub (60watts!) next, these HDDs fail on the powered hub as well.
 
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jz0309

Contributor
Sep 25, 2018
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my external HDDs have their own power supply ...
For giggles, I've erased my 8TB HDD that had been sitting idle for ~ 2 weeks now and started a TM backup, just under 3TB to go so it will likely finish when I'm in bed ... previously observed that initial TM backup completes but subsequent one fails. If it finishes before I go to bed, I will eject the drive and plug it back in tomorrow morning
 
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400

macrumors 6502a
Sep 12, 2015
760
319
Wales
I don't want to start the process again as it can take some time but my initial run of first aid failed week before last (then last week), it would not unmount the disk. I manually unmounted and it ran through the disk OK though 4tb and nearly full it took a while. Hence I don't want to start it again.

But I find the external hard drives seem flaky under Big Sur. Random disconnects, plug an external Bluray in the lot drops out randomly etc.

I have my Time Machine through a powered external USB3 hub and the time machine disk is in a powered case. Due to it holding old Catalina stuff, I re formatted and ran the Time Machine for the new Big Sur and then ran first aid after un mounting it myself, less data and it ran quicker obviously but does not seem to get past the unmount unless you do it first.
 

jz0309

Contributor
Sep 25, 2018
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Update from my latest experiment"
Full TM backup completed
Subsequent TM backup failed
Then a eject disk error occurs
1630167972906.png


I reconnect the hard drive and FirstAid fails
1630168043092.png

I start TM backup and it completes
1630168101539.png


While typing this, I plug the HDD back in and run FirstAid again, failure
At least there seems to be consistency with FirstAid this time
 

vett93

macrumors 6502
Original poster
Jul 27, 2014
279
40
California
Update: I have a new finding. The First Aid failure is not limited to just TM HDDs. I checked this morning a HDD that I used to store bulk data. (I am a Machine Learning software engineer by trade.) It also failed the First Aid test.

There seems to be issues with the current released APFS with HDDs. For those who have no problems, can you please post your configuration? What HDDs do you use? Thank you.
 

bernuli

macrumors 6502a
Oct 10, 2011
713
404
Are you using a usb gaming mouse or keyboard? I have had related issues in the past which I attributed to the high poling rate of those specialized devices.
 

vett93

macrumors 6502
Original poster
Jul 27, 2014
279
40
California
Are you using a usb gaming mouse or keyboard? I have had related issues in the past which I attributed to the high poling rate of those specialized devices.
No, I use BT mouse and keyboard. These are not designed for gaming.
 

vett93

macrumors 6502
Original poster
Jul 27, 2014
279
40
California
Are you using a usb gaming mouse or keyboard? I have had related issues in the past which I attributed to the high poling rate of those specialized devices.
BTW, can you please try First Aid on any existing spinning-disk drive you have under Big Sur 11.5.2? Please let us know if your HDD passes.
 

jz0309

Contributor
Sep 25, 2018
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29,878
SoCal
Experiment #2
erased and reformatted the 8TB HDD with APFS
FirstAid passes
Now using CCC to copy all my data

Will update once completed
 

vett93

macrumors 6502
Original poster
Jul 27, 2014
279
40
California
Let's know how it goes. I am doing another experiment as well. Instead of my 2013 Mac Pro, I am now testing it on my M1 MBP. This M1 MBP also runs Big Sur 11.5.2.

I erased and reformatted the same LaCie drive with APFS on the M1 MBP. Then I ran First Aid on it and it passed too. Now it is backing up the M1 MBP with Time Machine. Will run First Aid again.
 

vett93

macrumors 6502
Original poster
Jul 27, 2014
279
40
California
Update: My M1 MBP has no problem at all with the APFS formatted external HDD. This HDD failed on my 2013 MP. I moved the HDD to M1 MBP, erased it, reformatted it to APFS, tested it with First Aid and passed, ran TM backup, and then ran First Aid again. It all works.

My next test is on my 2019 MBP....

Screenshots from M1 MBP:
Screen Shot 2021-08-28 at 3.15.10 PM.png
Screen Shot 2021-08-28 at 3.15.30 PM.png
Screen Shot 2021-08-28 at 3.40.49 PM.png
Screen Shot 2021-08-28 at 3.42.56 PM.png
 
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jz0309

Contributor
Sep 25, 2018
11,318
29,878
SoCal
My CCC backup on my 8TB drive (APFS) still has 4.5 hrs to go, so will report results tomorrow.
I'll also plug it into my M1 MBA running Monterey, but I did that before and FirstAid showed the same random behavior ...
 

vett93

macrumors 6502
Original poster
Jul 27, 2014
279
40
California
Just finished the testing on my 2019 MBP. It failed as well. Now I have test 3 Macs and 4 HDDs. They all failed. A reasonable guess is that APFS on Big Sur 11.5.2 does not work well with HDDs.

I am surprised that some people do not have problems.
 

400

macrumors 6502a
Sep 12, 2015
760
319
Wales
Just tried a second time now I have time. The first test was with the disk mounted. It failed.
I ejected the enclosure and made sure the TM section was unmounted then run first aid and it is OK. Not ticked your poll as I get a fail and a pass.
It is now running through the snapshots and will be a while.
 

EuroChilli

macrumors 6502a
Apr 11, 2021
530
542
Belgium
Just finished the testing on my 2019 MBP. It failed as well. Now I have test 3 Macs and 4 HDDs. They all failed. A reasonable guess is that APFS on Big Sur 11.5.2 does not work well with HDDs.

I am surprised that some people do not have problems.

While you 'can' format a traditional HDD to APFS, it is much better suited to SSD drives, as that was Apple's original intention. The way the 2 types of drives read/write and handle data is in fact vastly different.

I've read a few explanations as to why APFS on an HDD is not the best idea since sliced bread, with any version of macOS since it (APFS) came out with High Sierra. Here's one:




Screenshot 2021-08-29 at 12.13.56.jpg



But to answer the original question; No TM backup disk problems on Big Sur 11.5.2, on an M1 Air.

However, I have a Samsung SSD T7 external formatted to APFS which contains my 700GB / 105k image Photos library, it is lightning fast, no problems. Then using Time Machine, I back that drive up to my regular 5TB Seagate HDD which is formatted mac os journaled (HFS+). Again, no problems.


This is my Seagate 5TB HDD, format HFS+:

Screenshot 2021-08-29 at 11.53.12.jpg



This is my external Samsung T7 SSD, format APFS:

Screenshot 2021-08-29 at 12.34.17.jpg

Screenshot 2021-08-29 at 12.26.11.jpg
 
Last edited:

jz0309

Contributor
Sep 25, 2018
11,318
29,878
SoCal
While you 'can' format a traditional HDD to APFS, it is much better suited to SSD drives, as that was Apple's original intention. The way the 2 types of drives read/write and handle data is in fact vastly different.

I've read a few explanations as to why APFS on an HDD is not the best idea since sliced bread, with any version of macOS since it (APFS) came out with High Sierra. Here's one:
When you start a new TM backup on Big Sur, eg a new or reformatted HDD, TM will reformat it to APFS case-sensitive regardless if the hard drive was formatted to APFS or HFS+. Not sure which OS version started that behavior
 

EuroChilli

macrumors 6502a
Apr 11, 2021
530
542
Belgium
When you start a new TM backup on Big Sur, eg a new or reformatted HDD, TM will reformat it to APFS case-sensitive regardless if the hard drive was formatted to APFS or HFS+. Not sure which OS version started that behavior

That's really odd behaviour, never head of TM forcing the format. I always thought you'd be offered the options, of which there are a few.


"If you select a new backup disk that’s not already formatted as an APFS disk, you get the option to erase and reformat it."




So it looks like Big Sur supports TM backups to APFS, but doesn't force it. What I can't seem to find is if it supports TM backups to APFS on regular spinning HDD's. I know for a fact Big Sur still supports TM backups to HFS+ HDD's, because I'm doing it without issues.

What I did, with Big Sur 11.5.2 on my M1 Air, was to first format the Seagate 5TB HDD to HFS+ using Disk Utility, then when I opened TM, I was simply asked if I wanted to use that disk for backups. I said yes, and that was it. The drive was not force re-formatted to APFS.

What I know about APFS is it does provide better performance, among other things on SSD's, but TM does not need performance, it just needs reliability, which is what I think HFS+ has provided, for the last 35 years.

In fact, I think using expensive high performance SSD's for Time Machine backups is a colossal waste of money. For the price of a single Samsung 2TB SSD, I can get 3x Seagate 4TB HDD's. That means I can keep 3 separate TM backups in 3 separate locations.
 
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