Time Capsule on Raspberry Pi

Running Time Machine Server on Raspberry Pi using an exFAT HDD

Inspired by macOS Backup Raspberry Pi als NAS mit TimeMachine

1. Add exFAT support

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}
  

2. Install Netatalk

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}
  

3. Restart Netatalk after boot

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
  

4. Spin-Down HDD on shutdown

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)

5. Find Time Capsule with macOS

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 :)

Sources

• 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