How to build a Time Machine backup with a Raspberry Pi that just works.

https://johnkimdev.github.io/raspberry-pi-time-machine-how-to

UPDATED: May, 2020

TOTAL INSTALLATION TIME: 30 mins (without RPi SD image download and flashing time)

Known Issue

If your Mac has an older MacOS, it may not able to find the Time Machine (Samba) drive automatically. I have two Macs, one with 10.15, catalina and another one with 10.11 El Capitan. Everything works perfectly on 10.15 but in 10.11, it was not able to connect to the RPi Time Machine drive. There are some suggested workaround solutions on Web but I will leave you to find out if you run into this issue. (FYI, I couldn’t make mine work on 10.11 either)

Hardware

Raspberry Pi 3, 3b, 3b+, or 4
8GB or more SD card
External USB Storage Drive (HDD, SDD, USB Drive, etc)
Wired/Ethernet (recommended) or wifi internet connection

Installation Steps

Download “Raspbian Buster with Desktop” https://downloads.raspberrypi.org/raspbian_latest and flash a SD card
- Windows/Mac/Linux SD Image Writer: https://www.balena.io/etcher
Start Raspbian OS > Menu > Preferences > Raspberry Pi Configuration > Interfaces (TAB) > SSH > Enabled > OK
Connect your USB external HDD
Connect a wired/Ethenet cable or setup a wifi for internet connection
Open Raspbian OS terminal or ssh to RPi ssh pi@<RPi_IP_Address>

Type the following commands in the terminal or SSH console.

 sudo apt-get update

 sudo apt-get upgrade

 sudo apt-get install gparted hfsprogs hfsutils hfsplus samba samba-common-bin

lsblk and the find the mountpoint of the external HDD, for example;

 NAME        MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
 sda           8:0    0  3.7T  0 disk /dev/sda
 mmcblk0     179:0    0  7.2G  0 disk
 ├─mmcblk0p1 179:1    0  256M  0 part /boot
 └─mmcblk0p2 179:2    0    7G  0 part /

MOUNTPOINT for the external HDD (in this example) is /dev/sda. <– NOTE THIS INFORMATION

External HDD Format: Continue type the command in the terminal

(Replace /dev/sda witht the mounting location information from STEP 7)
```
sudo umount /dev/sda
```
```
sudo parted /dev/sda storage hfsplus
```
sudo blkid /dev/sda and get the UUID of the newly formated external HDD. For example;
```
 /dev/sda: UUID="71eb5d27-232d-9438-a9f7-bcf23423e2fa6a" LABEL="untitled" TYPE="hfsplus"
```
UUID: 71eb5d27-232d-9438-a9f7-bcf23423e2fa6a <– NOTE THIS INFORMATION

Mounting and Configuration: Continue type the command in the terminal

(replace 71eb5d27-232d-9438-a9f7-bcf23423e2fa6a witht the UUID information from STEP 9)

mkdir /home/pi/shared

echo "UUID=71eb5d27-232d-9438-a9f7-bcf23423e2fa6a /home/pi/shared hfsplus force,rw 0 2" | sudo tee -a /etc/fstab

sudo mount -a

sudo chown pi:pi /home/pi/shared

sudo chmod 777 /home/pi/shared

Samba Configuration: Continue type the command in the terminal

sudo tee -a /etc/samba/smb.conf > /dev/null <<EOT
[TimeMachine]
comment = Time Machine
path = /home/pi/shared
browseable = yes
writeable = yes
create mask = 0600
directory mask = 0711
spotlight = yes
vfs objects = catia fruit streams_xattr
fruit:aapl = yes
fruit:time machine = yes
public = yes
EOT

sudo smbpasswd -a pi

sudo hostnamectl set-hostname TimeMachine

All done
```
sudo reboot
```

Test

From your mac, Settings > Time Machine

Comments

Step 1: Raspbian OS Image

You don’t really need a desktop version image of Raspbian OS. All installation steps above are for command line inputs. You can check out the download page for other image options. https://www.raspberrypi.org/downloads/raspbian/
If you don’t use a desktop version image, you can use a smaller size of SD card.
For the main backup storage, it might be a good idea to use 1TB or more drive
(TIP) When downloading an image from https://www.raspberrypi.org/downloads page, using a torrent option is much faster than the direct download.

Step 2: SSH

If you choose to use the minimal image (without desktop version), make sur to enable SSH during the setup.

Step 4: Wifi vs. Ethernet

You can use wifi, but an ethernet connection is better for speed and reliability.

Step 5: IP Address

one of the ways to find IP address is open a terminal and type ifconfig

Step 6: GParted

If you want to divide your hard drive or use a potion of the main SD card, it might be easier to use a GUI version, (if you are using a desktop version OS), go to Menu > System Tools > GParted

Step 10: Mounting Location

For mkdir /home/pi/shared command and other mounting location information /home/pi/shared, you can choose any location but it is important that you need to set the owner and permission.

Step 11: Samba Configurations

The long command sudo tee -a /etc/samba/smb.conf ... is SINGLE command, copy entire block of codes and paste and execute.
In the command of sudo tee -a /etc/samba/smb.conf ..., the text “[Time Machine]” (without brackets) will show up as a time machine name in a Mac Time Machine dialog. You can name it whatever you want.
sudo smbpasswd -a pi You can create multiple samba users, and it does not have to be the same username as a RPI SSH user. I just chose pi as a samba username to be consistent, but it can be anything. If you have multiple users at home and need to control each user’s usage access, it might be a good idea to create an account for each samba user.
sudo hostnamectl set-hostname TimeMachine This is an optional command. The RPi hostname shows up in the sidebar of a mac under “Locations”. The hostname can be anything but no white space or punctuation characters allow. https://en.wikipedia.org/wiki/Hostname

Post Installation: Initial Backup

It is normal to take a long time during the first backup process. It can takes hours (mine took over 9 hours). It is a good idea to run the first backup overnight with a wired (ethernet) connection. BTW it is OK to interrupt a backup process; it will resume during the next scheduled time. The backup process will be shorter after completing the initial backup.

My Final Setup

Raspberry Pi 3
Raspbian Buster with desktop image
SandDisk 8GB SD
Toshiba NAS N300 4TB HDD
Rosewill USB 3.0 eSATA 3.5” Aluminum SATA Enclosure