Running Time Machine Server on Raspberry Pi using an exFAT HDD

Inspired by macOS Backup Raspberry Pi als NAS mit TimeMachine

As there are no good options to use a HDD with APFS or HFS+ for read/write with a Raspberry Pi, exFAT is the filesystem of choice, as it can be read by macOS which is not possible for ext4 without any additional tools.

• Update dependencies

  sudo apt-get update
  sudo apt-get upgrade

• Install exFAT utilities

  sudo apt-get install exfat-fuse
  sudo apt-get install exfat-utils

• Format HDD with exFAT

  # replace {sdxn} with mounting point, e.g. sda1
  mkfs.exfat /dev/{sdxn}

For the Raspberry Pi to act as a NAS (Time Capsule) the program netatalk is required.

• Install netatalk

  sudo apt-get install netatalk

• Configure netatalk

  Add in configuration file /etc/netatalk/afp.conf (replace {NameOfHDD} with HDD name)

  [TimeMaschine]
  path           = /media/pi/{NameOfHDD}
  time machine   = yes
  valid users    = pi
  unix priv      = no

  To solve the problem that netatalk can't create directories on exFAT unix priv = no is required (Link)

• Restart netatalk and Raspberry Pi

  service netatalk restart
  sudo reboot

• Test service and drive mount (replace {NameOfHDD} with HDD name)

  ps aux | grep netatalk
  df /{NameOfHDD}
  mount | grep /{NameOfHDD}

As macOS doesn't recognize the backup drive after start adding a restart script is required

• Copy scripts folder to /home/pi/

• Enable system service to run restart.sh on startup

  sudo systemctl enable /home/pi/scripts/restart.service --now
  sudo systemctl daemon-reload

In order to spin down the HDD manually or on shutdown, another script is necessary

• Copy contents of desktop folder to /home/pi/desktop
• Replace {NameOfHDD} with HDD name in scripts/ejectHDD.sh

Now a manual eject of HDD or shutdown including spindown of HDD is possible using the desktop shortcuts. Therefore a capable cable is required as Startech eSATA/USB3 (only RevA is working, spindown with RevB doesn't work anymore)

However, macOS does not recognize the self-created Time Capulse until the unsupported devices feature is enabled

• Enable unsupported devices on desired mac to backup

  defaults write com.apple.systempreferences TMShowUnsupportedNetworkVolumes 1

• Open Time Machine, search for Volumes, select {NameOfRaspberryPi}.local

• Login with same credentials as used to login with the raspberry

• Create Backups and enjoy :)

• macOS Backup Raspberry Pi als NAS mit TimeMachine
• Raspberry Pi exFAT: Adding Support for exFAT File System
• Sharing exFAT drive via Netatalk, can't create directories
• How to Enable Support for HFS on the Raspberry Pi
• How to mount a HFS partition in Ubuntu as Read/Write?
• Mounting an APFS image in Linux
• Using a Raspberry Pi for Time Machine