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If you set Time Machine to use encrypted backups, it will create a fake disk that's really a directory tree with a bunch of gigabyte-sized binary chunks. This is safer because it doesn't require the file system to support anything fancy like symlinks or case-insensitive unicode file names. One downside is that restoring to anything other than a Mac is nontrivial.
This 100% - it’s funny how it’s actually more reliable in my experience to use the encrypted sparse bundle. I can sling it over to my NAS no problem. I’ve restored from one and everything was perfectly fine. YMMV of course
Unencrypted sparse bundles for TM can also be created for non-TM supported network locations.
The bigger question is why does Time Machine continue use a network file system for backups? It's so fragile you can't rely on it. It's gotten better in recent years, possibly due to APFS, but that just means somewhat longer intervals between disasters (wipe out and reinitialize, losing all your backups). A T.M. using a custom protocol to save and restore blocks would fail sometimes too, but not ruin all your existing backups.

edit: I use Arq for daily backups, but T.M. for hourly. When T.M. eventually craters its storage, I have robust dailies in the cloud, so no worries.

> The bigger question is why does Time Machine continue use a network file system for backups?

The problem is them fucking up. Every other popular backup solution that does it does it just fine. And doesn't hide failures silently

> The bigger question is why does Time Machine continue use a network file system for backups?

As opposed to what? When you need to be able to back up to a drive on your network?

Outsider perspective here (never used Time Machine), but my first thought is that rsync works amazingly both local and over the network. Can't imagine why it being over the network would be a problem. If it can resume a partial transfer and compare checksums to ensure a match, what's the problem?
I'm a big fan of SuperDuper [1]. I use it for daily differential backups to a secondary SSD. I don't get the hourly backups that TimeMachine has, but my SuperDuper backups are directly bootable in the event that my system disk dies.

I'm sure you could do the same with cron and rsync, but I can't be bothered.

[1] https://shirt-pocket.com/SuperDuper/SuperDuperDescription.ht...

This has been on my to-buy list for a while. Something I should probably do, because while recovery from the built-in recovery interface is fine, having an offline bootable backup is also great. It also doesn't interfere with having Time Machine be the "standard" backup.

I could probably setup a calendar appointment to dump a bootable image once a month to an external disk.

> I don't get the hourly backups that TimeMachine has, but my SuperDuper backups are directly bootable in the event that my system disk dies.

Well as long as Apple hasn’t broken that with an update: https://www.shirtpocket.com/blog/index.php/shadedgrey/youre_...

I have been trying to trouble shoot a Time Machine issue since upgrading to Tahoe. It is usb backup. So far none of the most recent stated fixes work.

An initial backup on newly formatted disk will run but very slowly. Perhaps reaching 100% but it never finishes. At some point the percentage will change and the backup will stay stuck at somewhere near 10%. Cancel backup and run it again. Gets to ~10% and stays stuck. Multiple drives. Re-fs'ed. Boot into safe mode. Networking off. Etc, etc. etc. The TimeMachineMechanic app doesn't have any revealing feedback. I can run a full tar backup to the same disks.

No idea.

I haven't tried backing up to a network share but really, it shouldn't be this difficult.

Clearly someone didn't test a bunch of edge cases when pushing this one out.

In a terminal window run

  log stream --predicate 'subsystem == "com.apple.TimeMachine" AND NOT (category == "LogLimits" OR category == "VolumeViewModel")' --info --debug --style compact
and then start a backup (either from the menu bar icon, the system settings panel, or "tmutil startbackup"). This will tell you what Time Machine is doing, and might give you some useful information.

  man log
where you can use "show" and a lookback period instead of "stream".

  man tmutil
is pretty decent documentation, although the glossary secdtion ("BACKUP STRUCTURE") is important to understand if reading the whole man page.

Some things to look out for are what filesystem your newly formatted external volume is (APFS might not be great for a single spinny disk, for example), and what version of USB is in use (friends don't let friends do USB 2 mass storage). With inexpensive external media it's often a cable or power supply issue, even if (as in your case) tar appears to work. Have you checked that the contents of the tar file are correct? Also, tar files tend to be streamed out to sequential LBAs, where smaller files and (in Time Machine backups) holes might lead to a different write pattern that the drive might not like. Maybe test with rsync -c instead of tar?

Time Machine is held in high regard for some reason (maybe the fancy scrolling interface when you look for files to restore?) but it's not really useable. It pretends that backups-over-the-network are a possibility but its completely unstable over the network and invariably decides the backup is corrupt after a few months and then tells you you have to start from scratch.
> Time Machine is held in high regard for some reason (maybe the fancy scrolling interface when you look for files to restore?)

There was a time in the past when Time Machine was reliable and well-designed. It made backups into a nice experience that were accessible to everyone.

If your only experience with Time Machine is the modern incarnation with all of the flaws and seemingly missing QA process then I understand how its popularity would be confusing.

macOS yearly updates haven't been great since they started but Tahoe is a new low.

Apple really needs to turn things around.

I had so many corrupted Time Machine backups over the years that I eventually just wrote an incremental backup script in rsync. I’m much happier.

Something like [1] can be inspiration.

[1]: https://github.com/perfacilis/backup

If you set your Apple device to beta updates for the previous release you can suppress the constant prompts to upgrade. Reduces the chance of accidentally upgrading.
Article title is a bit dramatic. The summary seems to be: for the 5% of users who back-up to a network share (rather than direct-attached storage like a USB hard drive enclosure), Apple's default SMB configs on Tahoe are strict and won't work out of the box with many common NAS solutions.

Apple should document such changes, but, looking at the post title, you'd think they were silently corrupting data during restoration.

Just for the record: I wanted to see your content, but I couldn't because in Spain when there's football they block most websites to "avoid illegal football IP lists"... LaLiga can block anything they want without any restriction, even you website which I doubt about it. I can barely navigate... I will read it later tomorrow. This why you might see 0 traffic from Spain.
I never trusted Time Machine, my primary line of defense is rsync to a server running ZFS with hourly snapshots, and weekly rotations of offsite drives. For bootable backups, Carbon Copy Cloner.
Tahoe backups to UnRAID's native Time Machine backup system (as described at <https://docs.unraid.net/unraid-os/using-unraid-to/manage-sto...>) does not work in UnRAID 7.2.3. It is not (solely) caused by Tahoe, however, because it did work in 7.1.4. <https://forums.unraid.net/topic/195091-time-machine-backup-d...>

mbentley's Docker image version of Time Machine—which I began using back when native Time Machine support was completely broken <https://www.reddit.com/r/unRAID/comments/16x3ddm/my_experien...>—which the post mentions is unaffected, and continues to work with Tahoe without configuration changes.

I use the same setup and was able to restore some files I recently deleted. My SMB settings in Synology were set to what the recommended settings were already. Not sure what happened in this person's case, but it also seems like he backed up and didn't test the restores. Which isn't good practice.
Time Machine has always been a bit ropey on SMB shares. I think it’s in part because it creates a disk image on the share then writes to that. This creates a lot more work and potential for things to go wrong.

If you want to backup across the network then it’s probably best to choose some third party software.

I suspect that Time Machine is no longer used by a sufficiently large % of their customer base for them to care, and they are slowly sunsetting it. They are quite aggressive about that sort of thing, so I expect it to to deprecated in favour of iCloud soon.
What is Apple’s QA process? Do they rely on some random set of manual tests that may or may not get run each release? There have been so many things that seem like one of the most valuable companies in the world would include in tests, but yet break or remain broken.

As an experiment, open Console and filter just errors and faults. Dozens to hundreds of “errors” will scroll by representing the normal operation of the system. (Either they’re not really errors and no one cares or they really are errors and Apple just leaves their systems broken). How can anyone think this is OK?

I haven’t upgraded to Tahoe. I have been a Mac power user for over 20 years, and it becomes less interesting every release. I came for Unix, the script ability, and 3ᴿᴰ party applications. Unix is an afterthought, script ability is all gated behind security gates, and modern apps seem like such a huge regression.

This happened to me and I finally ditched time machine for BorgBackup https://www.borgbackup.org/

Not as nice UI-wise, but at least it's stable

Also running Tahoe. Also backing up to SynologyNAS. Also have lost 'many' backup to unknown reasons (was it a new beta? Was it a new OS? , the NAS crash of 2025) whatever.

Also, I don't even have an /etc/nsmb.conf or /etc/smb.conf file on the mac ( Tahoe 26.3)

I think the last time I configured Time Machine for SynologyNAS I followed as many tutorials as I could and basically everything is working for both mine & my spouses machines. - until it crashes & I lose everything.

Apple has always had problems with SMB since they switched from one of the open-source implementations to one it internally developed, many yaers ago.

Then again, SMB especially in its newer versions seems to be a protocol developed by MS with one of its goals being to make third-party implementations as difficult as possible.

As someone from Tahoe, it makes me sad that the release with the worst reputation is named after my home region.
I still don't understand why people insist on spending good money on a closed, proprietary appliance when they can run a general purpose, flexible server such as running Samba and NFS that can be tweaked to solve a variety of edge-cases that no closed system can match.
I use TrueNAS as a Time Machine destination for multiple Macs running Tahoe. Seems to work fine with no local configuration changes. Just make sure in SMB global configuration you:

- Enable Apple SMB2/3 Protocol Extensions

And when creating the SMB share select Time Machine for purpose.

- they blew 2 of my hard drives so far. you keep it connected and it used to do hourly backups except now both my hard drives are dead

- i am too afraid to buy another one and connect only to find out the SSD gets killed in another week

- Anyone knows about this issue?

The author posted a fix, but how do I check if there is a problem in the first place?
I strongly recommend against Time Machine to NAS — just mentioned it in an article today as “works great, until it inevitably and catastrophically fails”.

Reliable for me is Kopia from Mac to S3 compatible volume (minio) on Synology.

On Tahoe my Time Machine was broken after the update. My backup target is on a QNAP NAS. I just had to set it up from scratch again and it worked. But it did cost me a few files I was trying to recover. So I feel this.
restic and kopia should work decently, if with a bit of setup, I think both can just mount backup as FUSE filesystem

The backup system that silently breaks when it doesn't like something in backend is not worth time

Apple should honestly just deprecate and remove it with the level of effort they put into Time Machine.

Look, face it, Time Machine is not really what Apple wants you to do. They want you to buy cloud storage and just store your documents (desktop and documents in iCloud Drive) there. Photos are in the photos app. Etc.

Maybe they should make a Time Machine cloud service to help them justify putting time into it just like iOS has cloud backups, which work incredibly smoothly. But it’s also possible macOS has too much baggage for that to work (then again, migration assistant also seems to work great.

Long story short, if you want this you probably should be working with a third party, something like tossing $5 a month at backblaze backup.

I’ve moved away from Mac and I’ve been having a great user experience with Pika backup, although it’s not quite analogous to Time Machine. Still, my Linux distribution is immutable, so backing up my home directory is pretty much the whole thing.

Another disturbing example of sloppy execution by Apple Software Engineering. This only reinforces my resolve to avoid upgrading to macOS Tahoe.
On Linux we get this for free with Btrfs copy on write snapshots, snapper, and Btrfs Assistant.
If you care about your data, don't trust a backup system that already failed before. This is simpler and easy to verify:

https://www.jwz.org/doc/backups.html

You can also get any AI tool create a good backup script for your particular setup.

What good is a backup if you're not checking it for months on end?
It reliably kernel panics since tahoe at a certain point
It's like they don't even care anymore
Somewhat related but I was disappointed to learn that Time Machine would no longer support Time Capsule post Tahoe, which I suppose is fair 8 years post discontinuation, but also unfortunate considering AFAICT the only real potential issue would be HDD degradation over the years? At the least, there have been plenty of system alerts noting this fact, but still annoying to have to buy something else. I know both AirPort and Time Capsule were an infinitesimally small part of their business...but they absolutely rocked when they were launched.
Apple software sucks nowadays
I upgraded to Asahi from Sequoia.
I have the same setup and it works fine on my machine. ¯\_(ツ)_/¯
Apple has broken Time Machine enough times that I would never consider using it at all anymore. Once upon a time, it was really neat, had great integration with Mac OS X, and an amazing user interface and experience, but it's now clearly technology that Apple will probably eventually drop entirely in favor of something less impressive all together, like telling you to buy more iCloud Storage.