Apple’s Time Machine has been around for years, and many Mac users still associate network backups with Apple’s older AirPort Time Capsule, AirPort Extreme shared disks, or network storage devices that supported Apple Filing Protocol, commonly known as AFP. However, AFP is now part of Apple’s legacy networking past. For anyone running a home lab, Linux file server, or NAS-style backup target, the practical replacement is SMB.
This article explains what is happening with AFP, why Apple is moving away from it, and how to configure a Linux Mint 21.3 server as a Time Machine backup destination using Samba and SMB.
What Is AFP?
AFP stands for Apple Filing Protocol. It was Apple’s native file-sharing protocol for many years, especially during the classic Mac OS and early Mac OS X era. It was designed around Apple’s file system expectations and supported Mac-specific metadata, resource forks, and other behaviors that mattered more in earlier generations of the Mac ecosystem.
For a long time, AFP worked well in Apple-only environments. It was commonly used by older Mac file servers, AirPort Time Capsule devices, AirPort Extreme USB disk sharing, and some third-party NAS appliances. Because Time Machine was originally introduced in the Mac OS X era, many older Time Machine network backup targets were built around AFP.
The problem is that AFP is no longer Apple’s preferred direction. Apple now clearly recommends SMB when a choice exists between SMB and AFP for Time Machine backups (Apple, n.d.-a). Apple also states that Time Machine backup to NAS devices over AFP is not recommended and will not be supported in a future version of macOS (Apple, 2025a). In macOS Sequoia, Apple has also stated that the AFP client is deprecated and will be removed in a future version of macOS (Apple, n.d.-b).
AFP Is a Protocol, Not a Disk Format
One point that causes confusion is the phrase “AFP disk.” AFP is not a disk format like APFS, HFS+, ext4, XFS, or ZFS. AFP is a network file-sharing protocol. When someone says that macOS will not support “AFP disks,” what they usually mean is that macOS will stop supporting network shares accessed through AFP.
The actual disk behind the network share might be formatted as HFS+, APFS, ext4, XFS, ZFS, Btrfs, or something else. The client Mac normally does not directly see that underlying filesystem. It sees a network share presented through a protocol such as AFP or SMB.
This distinction matters because the solution is usually not to reformat the Linux server’s disk. The solution is to stop serving the backup location through AFP and serve it through SMB instead.
Why Apple Is Moving Away from AFP
Apple’s move away from AFP makes sense for several reasons.
First, AFP is old and Apple-specific. It is not a broad cross-platform standard in the same way SMB has become. SMB is widely used by macOS, Windows, Linux, enterprise NAS devices, and general file servers.
Second, Apple’s modern file-sharing direction has been moving toward SMB. Apple’s own Time Machine documentation says that if a choice is available between SMB and AFP, SMB should be used for backup (Apple, n.d.-a). Apple’s Time Machine support article also says third-party NAS devices should support Time Machine over SMB (Apple, 2025a).
Third, Apple’s modern file system, APFS, does not align with an AFP-centered future. Apple’s APFS documentation states that APFS volumes can be shared using SMB or NFS, but not AFP, and identifies AFP as deprecated (Apple, n.d.-c).
Finally, removing AFP reduces the number of legacy components Apple must maintain and secure. Every protocol included with macOS has to be tested, patched, and supported. As AFP usage declines, it makes sense for Apple to consolidate around SMB.
What This Means for Home Labs and Linux Servers
If you run a Linux server and want it to serve as a Time Machine destination, you should configure Samba for SMB-based Time Machine support. Samba is the standard SMB server implementation used on Linux and Unix-like systems.
For Mac compatibility, Samba provides a module called vfs_fruit. The Samba documentation describes vfs_fruit as providing enhanced compatibility with Apple SMB clients. It can also advertise a share as a Time Machine-capable destination by using the fruit:time machine = yes option (Samba Team, n.d.).
In practical terms, this means a Linux Mint 21.3 server can replace an AFP-based backup target as long as Samba is configured correctly.
Example Goal
In this example, the Linux Mint server will provide a Time Machine backup share with these assumptions:
Server hostname: server1
Backup directory: /data/timemachine
Linux backup user: tmbackup
Samba share name: TimeMachine
Maximum advertised Time Machine size: 1T
You can change those values to match your own environment.
Step 1: Install Samba and Avahi
On the Linux Mint server, install Samba and Avahi:
sudo apt update
sudo apt install samba avahi-daemonSamba provides the SMB file-sharing service. Avahi provides local network service discovery using mDNS and DNS-SD, which is compatible with Apple Bonjour-style discovery (Avahi, n.d.). In many home networks, Avahi helps the Mac find the server automatically in Finder and Time Machine.
Enable and start the services:
sudo systemctl enable --now smbd
sudo systemctl enable --now avahi-daemonCheck that they are running:
systemctl status smbd --no-pager
systemctl status avahi-daemon --no-pagerStep 2: Create a Dedicated Time Machine User
Create a Linux user for Time Machine backups:
sudo adduser tmbackupThen create a Samba password for that user:
sudo smbpasswd -a tmbackup
sudo smbpasswd -e tmbackupThis account will be used by the Mac when connecting to the Time Machine share.
For a home server, it is usually cleaner to create a dedicated backup account instead of using your normal Linux login account. This makes it easier to control permissions and isolate the backup location.
Step 3: Create the Backup Directory
Create the directory that will store the Time Machine sparsebundle backup files:
sudo mkdir -p /data/timemachineSet ownership so the backup user can write to it:
sudo chown tmbackup:tmbackup /data/timemachineSet restrictive permissions:
sudo chmod 700 /data/timemachineThis gives the tmbackup user access while preventing other local users from browsing the backup directory.
Step 4: Back Up the Samba Configuration
Before editing Samba, make a backup copy of the existing configuration:
sudo cp /etc/samba/smb.conf /etc/samba/smb.conf.bak.$(date +%F)Edit the Samba configuration using vi:
sudo vi /etc/samba/smb.confAdd or adjust the following configuration.
[global]
workgroup = WORKGROUP
server role = standalone server
security = user
map to guest = Bad User
min protocol = SMB2
fruit:aapl = yes
fruit:model = TimeCapsule
[TimeMachine]
comment = Time Machine Backups
path = /data/timemachine
browseable = yes
read only = no
valid users = tmbackup
vfs objects = catia fruit streams_xattr
fruit:time machine = yes
fruit:time machine max size = 1TSave and exit vi.
A few settings are especially important:
min protocol = SMB2 prevents older SMB1 connections.
fruit:aapl = yes enables Apple SMB2+ extensions, which improve behavior and performance for Mac clients.
vfs objects = catia fruit streams_xattr enables the Samba modules commonly used for better macOS SMB compatibility.
fruit:time machine = yes advertises the share as Time Machine-capable.
fruit:time machine max size = 1T limits the size reported to Time Machine. This helps prevent Time Machine from assuming it can consume the entire underlying filesystem. Samba’s documentation warns that this value is an approximation based on Time Machine sparsebundle contents, so the share should be dedicated to Time Machine backups when using this option (Samba Team, n.d.).
Step 5: Test the Samba Configuration
Run:
testparmIf Samba reports no serious errors, restart Samba:
sudo systemctl restart smbdThen confirm Samba is listening:
sudo systemctl status smbd --no-pagerStep 6: Allow Samba Through the Firewall
If UFW is enabled on the Linux Mint server, allow Samba:
sudo ufw allow SambaCheck firewall status:
sudo ufw status verboseIf the server and Mac are on the same trusted home network, this is usually sufficient. If the server is exposed to untrusted networks, do not open SMB broadly. SMB should normally be limited to a trusted LAN or VPN.
Step 7: Connect from macOS
On the Mac, open Finder and choose:
Go > Connect to Server
Enter:
smb://server1.local/TimeMachineIf .local name resolution does not work, use the server’s IP address instead:
smb://192.168.1.50/TimeMachineLog in with:
Username: tmbackup
Password: the Samba password you set with smbpasswd
Once the share mounts successfully, open Time Machine settings on the Mac and select the network share as the backup disk.
On recent macOS versions, go to:
System Settings > General > Time Machine
Then add or select the SMB share as the backup destination.
Step 8: Encrypt the Backup from the Mac
When setting up the Time Machine destination, enable backup encryption from the Mac if available. This protects the backup contents if someone gains access to the server’s disk or copies the Time Machine sparsebundle.
Encryption is especially important for laptops because Time Machine backups may contain browser data, documents, email data, SSH keys, application data, and other sensitive information.
Store the encryption password safely. If you lose the Time Machine encryption password, you may not be able to restore from that backup.
Step 9: Verify That Backups Are Running
After configuration, start a backup from the Mac. On the Linux server, you can watch the backup directory:
sudo ls -lh /data/timemachineYou should eventually see a Time Machine sparsebundle created for the Mac.
You can also check Samba logs if something fails:
sudo journalctl -u smbd --no-pagerOr review Samba log files:
ls -lh /var/log/samba/Troubleshooting Tips
If the Mac cannot see the server automatically, connect manually using Finder with the smb:// path.
If the Mac can connect but Time Machine does not list the share, recheck that the share includes:
fruit:time machine = yesIf the share appears but backups fail, check permissions on the backup directory:
ls -ld /data/timemachineThe directory should be writable by the Samba user.
If name resolution fails, try the server’s IP address instead of the .local hostname.
If the backup grows too large, reduce the value of:
fruit:time machine max size = 1TThen restart Samba:
sudo systemctl restart smbdRecommended Practices
Use a dedicated share for Time Machine. Do not mix normal file storage and Time Machine backups in the same directory.
Use a dedicated Samba user for backups.
Use a wired connection for the first backup if possible. The first Time Machine backup can be large.
Use redundant storage if the backup matters. A Time Machine backup stored on a single failing disk is still a single point of failure.
Do not expose SMB directly to the internet.
Periodically test restores. A backup is only useful if it can be restored.
Conclusion
AFP served Mac users well for many years, but it is now a legacy protocol. Apple is clearly moving Time Machine network backups toward SMB, and future macOS versions will remove AFP support. For Linux server users, the practical answer is to configure Samba with Apple-compatible settings and enable Time Machine support through vfs_fruit.
A Linux Mint 21.3 system can work well as a Time Machine backup target when Samba is configured properly. By using SMB, a dedicated backup user, proper permissions, and the fruit:time machine = yes setting, you can replace an older AFP-based backup workflow with a more modern and future-ready configuration.
References
Apple. (2025a, December 5). Backup disks you can use with Time Machine. Apple Support. https://support.apple.com/en-us/102423
Apple. (n.d.-a). Types of disks you can use with Time Machine on Mac. Apple Support. Retrieved June 3, 2026, from https://support.apple.com/guide/mac-help/types-of-disks-you-can-use-with-time-machine-mh15139/mac
Apple. (n.d.-b). What’s new for enterprise in macOS Sequoia. Apple Support. Retrieved June 3, 2026, from https://support.apple.com/en-us/121011
Apple. (n.d.-c). Apple File System Guide: Frequently Asked Questions. Apple Developer Documentation Archive. Retrieved June 3, 2026, from https://developer.apple.com/library/archive/documentation/FileManagement/Conceptual/APFS_Guide/FAQ/FAQ.html
Avahi. (n.d.). mDNS/DNS-SD. Retrieved June 3, 2026, from https://avahi.org/
Samba Team. (n.d.). vfs_fruit. Samba Documentation. Retrieved June 3, 2026, from https://www.samba.org/samba/docs/current/man-html/vfs_fruit.8.html