After upgrade or new install of Big Sur, TM backup stoped working to Synology NAS using AFP or SMB3 protocol. TM to external USB works fire and other 4 mac's with Catalina can create TM backups to the same NAS without a problem.
MacBook Pro 13″, macOS 11.0
Here's what I did overall to get it working and it is now working on all my Big Sur implementations (4):
But before doing any of that take a look at the Connections log on your DSM (DSM>Main Menu>Log Center, and select Connections from the drop down menu. Check if when a Time Machine backup initiates whether you have more than one user attempting the connection. For example, I noted that when my backups failed I would have two (2) users that had privileges to that shared folder attempt to connect nearly simultaneously from the same Mac even though I had only supplied one user credentials when selecting the share in Time Machine setup. I have no explanation or even speculation as to why that was happening.
I suspect there is a bug lurking in Big Sur regarding Apple's choice of APFS Time Machine backups that causes it to not play well with NAS devices, or in particular Synology NAS devices. It won't surprise me in the least if this is addressed in an 11.1 release. Everyone knows the 11.0.1 release was rushed to coincide with the M1 Macs show, and may not still be ready for primetime. I have a Mac I use as an Apple Music/TV/Plex server that relies on a 24tb SoftRAID RAID5 array that I cannot transition to Big Sur until SoftRAID is able to release an update (they claim their updated driver is built into the Big Sur release, but users are reporting issues and the client is beta and will be for some time). I'm just not going to risk that machine to some fatal bug that totally borks a 24tb array.
I haven't seen any specific mention of AVG causing the same problem, but I would bet that *any* third-party anti-virus software on Big Sur blocks Time Machine. It would be worth a try to uninstall AVG, reboot, then try Time Machine again.
Sophos Home blocked TimeMachine on a NAS and removing it worked for me.
I have now installed Bit defender instead as an anti virus checker and everything including TimeMachine is still working normally on the NAS.
I can now confirm that uninstalling Sophos Home and rebooting both my Mac and my NAS solves the problem. I can also confirm that you can install BitDefender on macOS Big Sur, and Time Machine continues to work to backup to NAS. It is the one anti-virus I've heard about so far that does not clobber Time Machine.
Follow-up to this. As I said, I don't have Sophos installed, but I have solved this I think. Simply removed old TM directory on NA. Disabled AFP, enable SMB. Set-up new TM directory with specific user/priviledges. Connect TM to this as new backup source with new TM-only user credentials. This innitiated the first backup, which at 854GB may take some time!! Will report back when I get this done and resume daily backups...
This isn't specific to Synology NAS devices. I just replaced a WD My Cloud EX2 Ultra with a Synology DS218+ because of this issue and Big Sur Time Machine fails on both. Both work when running Catalina Time Machine. Pretty sure this is a Big Sur issue. I am considering abandoning Big Sur and going back to Catalina at this point.
It's an issue with certain third-party anti-virus and anti-malware software. After replacing Sophos Home with BitDefender on Big Sur, Time Machine runs with no problems to my WD My Cloud EX2 Ultra. It's not a problem on Big Sur, per se. It's third-party software that's now incompatible that blocks Time Machine.
I removed Sophos Home in an earlier attempt to fix this. Even with no anti-virus or anti-malware it continued to be an issue. Cautious optimism follows! I have since found a setting in the Synology NAS that seems to have it working right now. I turned off the option File Services>AFP>Advanced>Release resources immediately after disconnect. It's been backing up 30 minutes already without stopping. It makes sense that an AFP setting would make some difference since Time Machine in Big Sur apparently prefers AFP over SMB. That change has not affected backing up from my iMac running Catalina either since it apparently uses SMB to backup.
Yes, I've seen other postings mention having to tweak settings on Synology boxes to get it to work. On WD My Cloud, when I set up the box for Time Machine, it automatically turned on AFP with no other options. If I turn off AFP, it resets the box to not be visible to Time Machine. Very simple.
I followed all of this and still had an issue. What I found that worked for me was to navigate to File Services>AFP>Advanced Settings and cleared the check mark on "Release resources immediately after disconnect" and finally hit Apply. This kinda makes sense based on what i've been seeing in the TM logs and that Big Sur TM prefers AFP to SMB. I was finally able to get a complete backup of 900 GB in about 5 hours over Ethernet.
Good article covering this topic at https://eclecticlight.co/2020/06/29/apfs-changes-in-big-sur-how-time-machine-backs-up-to-apfs-and-more/ ... I have the same problem as I upgraded one of my MBPs to Big Sur today :-(
rolandwartenberg wrote:
Good article covering this topic at https://eclecticlight.co/2020/06/29/apfs-changes-in-big-sur-how-time-machine-backs-up-to-apfs-and-more/ ... I have the same problem as I upgraded one of my MBPs to Big Sur today :-(
This does not relate to Synology backups which are network backups and not using either APFS or HPFS volumes. It is more like a local process related to anti-viruses on the Mac is blocking Time Machine in creating a remote backup.
Most NAS devices use either AFP or SMB. My NAS sets up any share for Time Machine as AFP, so yes, this impacts my backups. I found that Sophos Home was blocking how Time Machine wanted to use the AFP share.
As far as Big Sur is concerned, everybody needs to forget AFP as it has been deprecated. Also, everybody needs to get off the concern regarding APFS with respect to network backups - as those drives are not formatted in APFS. The issue is third party antivirus/malware protection, and in particular, at least in my case, Sophos. Sophos has documented that it breaks Time Machine network backups, and still has inexplicably failed to fix it. In about 20 seconds I'm going to dump them forever.
Hi,
I meanwhile tested successfully that AFP on an upgraded Big Sur system (from Catalina) is still working whereas it's not anymore on a fresh installed Big Sur (which I did the other day as a test). Looking at other articles like https://www.synoforum.com/threads/mac-os-big-sur-drops-afp.4717/ I will now set up a complete new backup set on my NAS using SMB.
Best
Roland
This was my experience as well: an install of big sur from within catalina was able to connect to and back up to my DS416 using a user's credentials. however after a fresh install from bootable media including a wipe of the drive in a MacBook Air circa 2015 followed by a migration from an older machine, and the machine has the symptoms reported here being what looks like instant pairs of connection requests in the logs every time it tries to back up. and a failure every time as well. I'll assume some kext or bit or bauble contained in Catalina stayed in the install-over, and once I did the clean install that magical little nub of driver or code or whatever was wiped out. 🤷♂️
TimeMachine Big Sur to Synology NAS
