Time Machine backup on macOS Sequoia cannot be completed

Just tagging in to say "same". Only when sleep. When awake again is fine. So would appear to be some state change in something(s) somewhere that blocks some process.

FWIW, this is to a Fantom Thunderbolt drive, not finding specs at the moment, APFS. Info shows as Bootable=No, Journaled=No, SMART=Not Supported,not encrypted,Ejectable=Yes. Looks like I have it hanging off a OWC Thunderbolt Hub USB4.

Time Machine is always a bit sluggish, but that's quite a while. How old is the Mac? Was the disk nearly full? If it has decided to clear out some old backups it would take a while on an older machine. Are there any clues in Activity Monitor?

Just to follow up. I'm still working with Apple engineers on this. There were a couple weeks of ghosting me but eventually they replied and last week logs were taken and I'm waiting for my rep to get back to me on next steps/conclusions, etc. I also updated the firmware of my Samsung T5 and T7 drives which was a challenge in itself, but did not resolve the issue so hopefully that eliminates them saying it's Samsung's issue. ;-)

More to follow when I hear back.

I have the same issues with my new m4 mac mini 15.1.1 and my WD ex2 ultra. fails to backup a different random file every time. Seems like apple admit there is an issue. tiem machien worked fine on the same nas on my old mac, (big sur).

That's a helpful observation and a reminder that similar symptoms may result from multiple causes. For those of us backing up to a NAS that is otherwise working fine, but failing to complete the backup we will need to seek further.

Since 15.0 (now on 15.2), it is also failing for me when the Mac mini M2 gets locked.

But that is not even my main problem. My problem is that the "preparing" phase now takes over 1 hour and the "cleaning up" phase also seems to be slower. Before 15.0, a TM backup usually took 10-15 minutes altogether.

I do not have the file "/etc/nsmb.conf" on my Mac mini and the firewall is off.

Hi med8or,

I have this problem with Time Machine, at first I thought it was the external disk(s) I was using they were not to date (2 years old).

Now I have purchased a brand new branded external disk, this fault is exactly the same and with the two others sitting on the side, because the same thing happened when I copied folders and moved them from one disk to another.

I would have thought by now this would have been rectified especial with all the M4 Macs going out due to there release.

it has taken the edge of purchasing my new Mac mini, as backups are critical to me.

I just wish I read read this post sooner - it would have saved me £160.

Adding TMHelperAgent.app to the firewall options app list solved the issue for me (MacbookPro 16" M1 Max). I had set TM to backup daily to avoid the repeated failure notifications. Now, its back to the default hourly schedule with no issues reported while idle.

I would suggest doing more research before resorting to random unfounded suggestions. Sequoia absolutely supports HFS+, APFS is not "Sequoia's file system" (but was rather introduced in macOS Sierra), and you give no reason why this should work.

There are a lot of unfortunate placebo suggestions here that appear to fix the buggy behavior only to fall back to square one a short time later.

Same here. I just updated from Ventura to macOS 15.2 Sequoia and I'm getting "Backup not completed, Syncing happens when your Mac is turned on and connected to the Internet. Syncing may take a few days. Syncing will happen more quickly while your Mac is connected to a power source."

I only have one Apple ID and it's the same on my phone. I keep most of the cloud stuff off. I even tried disabling the "connect to cloud " on this Mac mini and it turns on by itself. It's ignoring my settfings. I did a Time Machine backup before I upgraded to Sequoia and had no issue. I've been a windows user my entire life. I can't stand this cloud stuff. I like doing this manual. I don't like how apple does everything for me and I don't know where the stuff is going. I see everything and every path with my other OS. I only have a Mac for Logic. That's it.

Now you’ve got that off your chest, you might get a better response if you asked a question focussing on your system configuration and which of the things you’ve tried and haven’t worked. Probably useful to say what you think the cloud has to do with it.

HI.

I have used the TimeMachine on my M2 2022 Macbook Air to connect samba 4.11.5 on Linux server.

My mac is updated to Sequoia 15.3, yesterday; However Timachine backup continues to fail it.

For watching Linux server access log, my mac connect to Linux server every 1 hour (by Timemachine.app confiugration).

I tried to type this command on Terminal app.

tmutil listbackups

The result was ''No machine directory found for host.''.

I have the same 'waking from sleep' problem with TM reporting it could not complete the backup, even though I am now on MacOS 15.3. I hope we can get a fix to the OS soon. Again, it doesn't prevent the TM backup because it resumes on waking, but it is frustrating to be faced with this message every time on waking my computer.

Unfortunately, this bug persists for me with 15.3 (and 15.3.1). I just woke my monitor and the backup error was present. Time Machine is presently running without issue since my monitor isn't asleep. I'd note I don't have disks set to sleep, etc. This is directly correlated with the displays being off.

I have selected "Prevent automatic sleeping when the display is off", "Wake for network access", etc. in an effort to nail down what might be causing since Apple introduced this issue with Sequoia. I'm stumped. It's an annoyance, but not the type of thing Apple should tolerate.