Sequoia Time Machine Synology NAS keeps disconnecting

Thank you for posting your experience. so you essentially re-did the macOS<>synology time machine integration and it's still not working the same as it was prior to the update from sonoma to sequoia? new folder, proper time machine folder settings, create the new time machine backup, etc... you did all that and it's still not working? ughhhhh

For me, that's always been the workaround that i've found solves these problems after a new macOS update. When macOS updates, can't think of a year that I wasn't forced to completely reintegrate time machine with my synology. it's always awful every year, but at least it still works in the end... not this time tho?

Sorry to get peoples' hopes up. My iMac failed to back up this afternoon when I was away and gave the same error about the Synology being disconnected.

So the 'fix' doesn't do anything. Don't waste your time if you haven't started.

Synology have asked me to provide them with a log of the failure so, just as soon as the next backup fails I will share the log information with them and with Apple.

Back to my SanDisk SSD for backups!

I am afraid the problem is on Apple's side.

I have a Synology DS218+ at home, and I have this issue with my MacBook Air recently updated to Sequoia.

I have never had any problems with a Network Time Machine backup (I have three going at the moment). I also don't have Synology anything. It sounds to me that it is on Synology's side.

I am having EXACTLY the same problem with both my MacBookAir M2 and with my iMacM1, both on Sonoma, and either when they back up on the Synology NAS (DS218+, 7.2.2) or on an old Airport Time Capsule. This started after the Sonoma upgrade and seems to happen when the computers are inactive/sleeping. I have the impression the backup might start, but then it is aborted because the Mac goes to sleep and cuts off the connection. Files "unavailable" and backup tha will resume "when your Mac is unlocked" let me think about an issue on the mac/sonoma side.

Mike Richards2 wrote:

Is anyone getting this fault on Apple processors?

FWIW. I'm not getting any errors with my 2024 M2 Pro Mac mini (running macOS Sequoia 15.0.1) that I use a Synology DS916+ (running 7.x DSM) for Time Machine.

Hi everyone,

Back from vacation hoping that 15.0.1 would fix the issue on my iMac Pro - and no such luck. The firewall is off, but the backups aren't completing - I'm now getting a selection of errors - either Time Machine tells me the sparsebundle is in use or it reports that the drive has disconnected.

I'm chasing Apple who are meant to have got back to me with more information after I sent them a whole bunch of logs, if they have anything useful to say I will share it here.

That thread is a different topic, but yes, related: sometime when a TM backup to a Synology fails because of a network disconnect, the TM disk image becomes stuck in a "in use" state so backup never restarts.

yes, I'm having multiple errors on M1 Max Macbook Pro, mostly around the backup not completing due to disconnection -- also just got a "disk not ejected properly" notification after the backup failed. Periodically the Finder will not access NAS content; this seems to coincide with mounting my iPhone16 and/or having a VM running Windows for ARM.

@tmelander,

This helped me. Thank you very much.

More thoughtlessness from Apple. Firstly, it shouldn't be missing from the default installation. Secondly, you can't even add this smbd process easily from System Settings. It's so locked down that you can't search for it in the location window that appears. You have to use a separate Finder window, open a folder here: /usr/sbin and then manually drag the 'smbd' app into the System Settings location window. "It just breaks" is the new slogan.

Im having a similar issue. We use a Synology Nas to edit footage from. Its been fine for near on 2 years. I updated (mistake) 2 weeks ago and then all of a sudden monday monring the server is disconnecting whenever it needs to do something ie: Exporting a video, reading the timeline, importing photos. It doesnt seem to matter about the file size. It just disconnects. Any ideas here? its only an issue with the NAS. Other drives like the Black Magic Cloud unit is fine. Also transfer speeds have slow right down

Hi BlueJayNE,

I don't think it is related to MAC address selected, in my case I used fixed one and it works or fails just depending on having firewall enabled or disabled.

After reading your comment I have given a chance disabling the WIFI MAC address privacy and results remain the same, that is Time Machine Backup works or fails depending on the Firewall status.

Maybe others can try and share their experiences.

Hi everybody.

Glad to hear other people are finding the firewall solution works.

Sadly, not the case here - my iMac Pro is still failing to complete backups with Time Machine reporting the networked Synology is disconnecting (it isn't). I've never had firewall turned on and it is most definitely turned off.

Apple never got back to me as they promised, so I guess I will need to start the whole task of raising the issue and having it escalated again.

Obviously, I will report back if there are any developments.

I upgraded my macbookair M2 to 15.1. It is not helping. I get the error "time machine did not finish backing up because some files were unavailable. Backups will resume when your mac is unlocked".

I am convinced there are two issues affectingTM backups: the first, linked to firewall etc. which appears to be solved by 15.1, the second has something to do with "sleep" or inactivity control. If the mac goes to sleep or is inactive during backup, the error shows up. No way out...

Glad to hear some people are getting backups after upgrading to 15.1. My iMac Probackups to a Synology NAS are still falling over with the disconnection error when the machine is unattended and has gone to sleep during a backup.

I have sent a whole lot of log data to Apple engineers at their request and am waiting for a response.

Sigh.

Is anybody still seeing the issue? Ever since upgrading to Sequoia, my SMB share on my Synology keeps on disconnecting after sleeping. I'm not using Time Machine unlike most people here, but I have the same symptoms.

My Synology is pretty old and is on DSM 6.2 and I figured it might just be that, but I tried creating an SMB share on a Freebsd and got the same behavior.