My Time Machine backups were working fine until I updated to 15.0.1. Now I constantly get:
The NAS is working fine. I have restarted my Mac and restarted the NAS. Just stopped working after upgrade to 15.0.1.
Mac Studio (2023)
So here's more information from my side.
I use TimeMachine as a convenience, not my only backup option. I've been to this rodeo before with Apple and TimeMachine.
My system wasn't failing to connect to the Synology or the backup data. Everything connected fine. The backup access was long enough to copy 6.5 MB then failed.
After forgetting the target disk and reconnecting it, the OS properly recognized that a prior backup existed, then asked if I wanted to delete the backup history, which sounded like it was different than the actual backup itself. I thought it was just going to delete all the indexes to the backup data and that during the backup process those indexes would be recreated. My Bad.
While fiddling with it a bit more I was watching connections to the Synology.
The Backup starts, creating one SMB3 connection to the Synology.
Then about 5 minutes in, while the TimeMachine application in Settings is still doing the "Cylon bar" & Preparing the backup. There's another SMB3 Connection made to the Synology.
About 90 seconds or so after that, the newer connection is closed.
A few minutes after that, TimeMachine reports that the connection to the backup disc was lost and that the backup failed.
I'll let Apple worry about it. I've spent way too much time over the years being an unpaid Software Quality Assurance person for them. I am a career SQA guy so I'm a bit mercenary about it.
I reported it so that other people who might rely on TimeMachine didn't lose their minds, or their data, trying to fix a problem Apple introduced with 15.0.1
Apple broke it, it's their backup system, it's their OS, they can diagnose and fix it.
This option works for me too.
But it's happening since the update to MacOS 15.0.1. So Apple should fix this problem I think!
Same issue here, usually making backups with TimeMachine to a Synology shared NVMe USB-C Drive without any problem. After upgrading to Sequoia 15.0.1 Final Release, TimeMachine crashes randomly seeing also High CPU utilization few seconds before. We have this enormous issue + Calendar Widget Language issue. This is the quality expected on a Final release?
Time Macine to me is very basic because at every Mac upgrade Time Macine will start ove like it was first time! It does ever sense Tome Machine was included and I come to consider it very basic backup! You would be better off using some well know third party backup programs that could handle Mac OS upgrades!
Yep- same for me. At least it works some of the time, so an improvement, but my mileage is that some TM backups work and some fail with "Some Files are in use/unavailable". Disappointing QA from Apple, but at least I've got *some* backups now on 15.2!
It's apparently fixed with 15.1 and later. I have no problem with TM with my 2024 Mac Mini M4 running 15.1 that came with it and then updated to 15.2.
@DL: your case seems to be a bit different than mine. But I found a solution and Time Machine backups are now working. I had to remove my Time Machine target in the System Settings and had reset the broadcast setting on the NAS:
After that Time Machine found the Time Machine target and I could re-attach to the backup and continue.
Same thing on a brand new M2 Max Studio running MacOS 15.1.1. No problem on an early M1 iMac also running 15.1.1. Playing with locking settings to see what happens given that the failure occurs when TM runs after hours of computer idling.
I agree that Apple must fix this as some of us rely on TM for backups.
Nope! Still not working.
Switching off firewall does not resolve the issue either.
Excluding onedrive and Dropbox from back up worked.
Thanks but your suggestions didn't help other than it caused the destruction of the entire backups. So I guess there's no problem now since there's no backup left to worry about. Oh Well.
After destroying the backup, new backups fail during creation.
If you have anything important in your backups I'd suggest that you either don't update quite yet, or turn off TimeMachine then wait for Apple to figure out what they've broken and what they need to do to fix it.
When I start the backup with the firewall off, the backup to the synology NAS works fine, albeit very slowly.
As soon as I turn the firewall back on, while the backup is running, the backup crashes with the following message:
Time Machine could not complete the backup to 'TimeMachine_bck_share'
The network drive was disconnected from the Mac during a backup.
Make sure the computer and the backup drive are on the same network and that the backup drive is turned on.
The strange thing is that the Network Drive is just accessible.
But apparently not for the timemachine application.
For me it's nearly the same Issue on M2-Mini 15.0.1. Before the update, TM was working fine.
On my QNAP-TS221 NAS, a TimeMachine Backup (manualy started) stopps with Message 'Network Disc was disconnected during the process' after many many minutes. Before it was always in mode 'prepairing the Backup'.
The Firewall on the M2 is and was always OFF. So this trick, didn't work for me.
Now I tried to just copy some files (25GB) to the NAS Share. The first attempt also stopped after some MBs without any message. The second attempt, during the MB Air was doing his TM-Job, now finished completly fine. After that, i tried once more to start a TM-Task on the M2, but stays still endless in 'prepairing the backup' mode.
On my old MB Air (MACOS 11) the TM-task seems to work fine, although very slow (more than 1h for 40GB, but it's on WiFi )
Is this Community here, the right place to tell apple about this problem? Or should we place it somewhere else?
Just to add I've had this problem too. I've been back and forth with Synology as I'd just (coincidentally) upgraded my NAS at about the same time as the MacOS update, and as there are quite a lot of errors in the Mac logs relating to Time Machine not being able to access the SMB share I believed this was a Synology thing.
However, I have disabled the firewall on my Mac and finally (after about 10 days back and forth) the Mac is backing up to the NAS. Not sure the full implications of the 'shields down' since I have a firewall running on my Ubiquiti gateway.
Here's hoping for an Apple solution soon, in the meantime the disabled firewall workaround is holding up for me.
Time Machine is not really my data backup solution, because as you imply, it's needs too much hand-holding to be reliable. My files etc are backed up elsewhere on the 3-2-1 principle. But TM really does work well to get you up and running again when you change your hard-drive or SSD or do some other destructive upgrade, without having to set everything up again from scratch.
Anyway - we digress :-/
Since update to MacOS 15.0.1 Time Machine backups do not work
