macOS Tahoe 26.3 introduced a compatibility issue with several Samba versions commonly used on Linux NAS systems.
If your Mac suddenly started having trouble accessing SMB shares, or if Time Machine backups stopped working, the cause may be an older Samba release.
This guide explains the issue and shows how to fix it by upgrading Samba on Ubuntu. The example environment uses a Raspberry Pi server running Ubuntu 25.10 and a Mac Mini M4 client, but the same approach works for most Linux NAS setups.
TLDR
macOS Tahoe 26.3 broke compatibility with some Samba releases.
If your Mac cannot access SMB shares or Time Machine stops working, check your Samba version. Versions 4.21 and early 4.22 builds are affected.
Upgrade Samba to 4.22.6 or newer, or 4.23+ to restore compatibility.
On Ubuntu:
sudo apt update
sudo apt upgrade samba
If your distribution ships an older build, install the upstream Samba repository and upgrade from there.
Quick fix
If macOS Tahoe 26.3 suddenly stopped working with your Samba server, the most common cause is an older Samba version.
Samba versions 4.21 and early 4.22 builds contain a regression that breaks some macOS SMB operations, including Time Machine backups.
Upgrade Samba to 4.22.6 or newer or 4.23+.
If your distribution does not yet include the fixed version, add the upstream Samba repository and upgrade.
The rest of this article walks through the full process.
Tested environment
This fix was tested with the following setup.
Client
• Mac Mini M4\ • macOS Tahoe 26.3
Server
• Raspberry Pi\ • Ubuntu 25.10 (questing)\ • Samba 4.22.3 upgraded to 4.23
The same solution should work for most Linux NAS systems running older Samba releases.
Example setup
Client
- Mac Mini M4\
- macOS Tahoe 26.3
Server
- Raspberry Pi\
- Ubuntu 25.10 (questing)\
- Samba file share
{=html}
<!-- -->
Mac Mini (Tahoe 26.3)
|
| SMB
|
Raspberry Pi
Ubuntu 25.10
Samba
Even though I do not use Time Machine on this share, the Samba version still needed upgrading to stay compatible with current macOS behavior.
Why macOS Tahoe 26.3 breaks older Samba versions
Recent Samba releases changed how certain file rename operations behave. macOS relies heavily on those operations when interacting with network shares.
These operations are used for things like:
- Time Machine sparsebundle management
- metadata handling
- extended attributes used by macOS
A change introduced in early Samba 4.22 builds unintentionally broke part of this workflow.
Later Samba releases restored compatibility.
The fix appears in:
- Samba 4.22.6 and newer
- Samba 4.23.x
Unfortunately many Linux distributions shipped earlier 4.22 builds.
For example:
samba 2:4.22.3+dfsg-4ubuntu2.2
That version falls directly in the affected range.
Check your Samba version
Run:
smbd -V
or
apt policy samba
Example:
Installed: 2:4.22.3+dfsg-4ubuntu2.2
If the version is earlier than 4.22.6, upgrading is recommended.
The clean way to upgrade Samba on Ubuntu
Instead of compiling Samba manually, use the official Samba upstream APT repository.
Benefits:
- keeps your system compatible with macOS
- preserves Ubuntu package management
- allows unattended upgrades to continue working
Step 1. Create a keyring
sudo mkdir -p /etc/apt/keyrings
curl -fsSL https://download.samba.org/pub/samba/samba-pubkey.asc | sudo gpg --dearmor -o /etc/apt/keyrings/samba.gpg
Step 2. Add the Samba repository
For Ubuntu 25.10:
echo "deb [signed-by=/etc/apt/keyrings/samba.gpg] https://download.samba.org/pub/samba/stable/ubuntu questing main" | sudo tee /etc/apt/sources.list.d/samba.list
Step 3. Update packages
sudo apt update
sudo apt upgrade
Verify the upgrade
After upgrading:
smbd -V
Expected output:
Version 4.23.x
At this point the Tahoe compatibility issue should be resolved.
Because the repository is now part of your APT configuration, future Samba updates install normally, including through unattended upgrades.
Optional configuration for Time Machine
If you use Time Machine over SMB, ensure your share includes the Apple extensions.
vfs objects = catia fruit streams_xattr
fruit:time machine = yes
fruit:metadata = stream
fruit:model = MacSamba
Without these options, Time Machine may behave unpredictably regardless of the Samba version.
If the upgrade does not fix the problem
In some cases Tahoe issues are triggered by unrelated edge cases.
Check the following:
- Mac name contains unusual characters
- APFS backup disk is nearly full
- macOS cached an old SMB session
Restart Samba:
sudo systemctl restart smbd
Reconnect from Finder:
Finder → Go → Connect to Server
Why this solution works well
Tracking the upstream Samba repository keeps your server closer to the current Samba release cycle.
This avoids the situation where:
- Apple updates SMB behavior
- Linux distributions lag behind upstream fixes
For home NAS systems and Raspberry Pi servers, this approach keeps macOS compatibility simple.
In practice the fix takes only a few minutes.
Frequently asked questions
Why did macOS Tahoe break Samba shares?
Tahoe exposed a regression introduced in early Samba 4.22 releases involving rename operations used by macOS backup systems.
Which Samba versions are affected?
Affected:
- Samba 4.21.x
- Samba 4.22.0 through 4.22.3
Fixed in:
- Samba 4.22.6+
- Samba 4.23+
Does this only affect Time Machine?
No. Time Machine failures are the most visible symptom, but other macOS SMB operations may also be affected.
Can I wait for Ubuntu to fix it?
Yes, but distribution updates sometimes lag upstream Samba releases. Using the upstream repository ensures earlier fixes.
Conclusion
If macOS Tahoe 26.3 suddenly stops working with a Samba share, the most likely cause is an older Samba release.
Upgrading to Samba 4.22.6 or newer, or 4.23+, restores compatibility.
This guide documents a real setup using a Mac Mini M4 and a Raspberry Pi server running Ubuntu 25.10.
Fortunately the fix is quick and straightforward.