Apple Time Machine and Netatalk 3

This is really about setting up Time Machine to do OS/X backups. OS/X can't use Samba with Time Machine, so that's not good enough.

Update 2017, it's Docker time!

I am now using docker image now that has netatalk and avahi in it. Much simpler once you find the right image on the Docker Hub. It's on Laysan right now instead of Tern, I did not see a reason right now to run a separate server just to support Timemachine. Laysan is a desktop so it is often sleeping at night but then, so are the Macs. Timemachine is resilient. It turns out Laysan is powered up now more often than Tern was.

Get the image!

docker pull mbentley/timemachine

Do some housekeeping,

sudo mkdir /var/log/timemachine
# Inside the docker container, group 1000 maps to "timemachine". 
sudo chgrp -R wildsong /volumes/timemachine/*
sudo chmod g+ws /volumes/timemachine/*

Start the image,

docker run -d --restart=always \
  --net=host \
  --name timemachine \
  -v /volumes/timemachine:/opt/timemachine \
  -v /var/log/timemachine:/var/log/supervisor \
  -e PASSWORD=mysecretgoeshere \
  mbentley/timemachine:latest

Any moment now, Laysan will show up in servers on my Mac... so cool. So much easier than building from sources...

Once I can see the machine in Finder under "Shared", I click on it and click on "Connect" and enter credentials, user "timemachine" and password "mysecretgoeshere" (or whatever you chose above) and you should be able to see the TimeMachine share. I save the credentials to my keychain by checking the appropriate box, so I don't have to enter them again in TimeMachine.

Since this is the third iteration I already had backups on the drive so I was able to remove the old entry for Tern and add one for Laysan. If it were a fresh empty drive I'd have to create a sparse bundle first. Not going to talk about that yet, later when I get another Mac I will no doubt come back and update this page again.

Explanation: I mount a pair of 3TB drives formatted with btrfs as a single filesystem at /volumes/timemachine. I put the local log file is in /var/log/timemachine. You have to use --net=host so that this docker can use avahi discovery; otherwise your Macs will not be able to find it in Timemachine. I set my own password to override the default "timemachine".

Once it's running you should be able to see the log files showing it's working, look in /var/log/timemachine.

cd /var/log/timemachine
cat netatalk.log
Apr 26 16:43:33.613717 netatalk[11] {afp_avahi.c:80} (info:AFPDaemon): Registering volume 'TimeMachine' with UUID:  '0795EE37-6397-9B09-00DE-5EB14448BE4D' for TimeMachine
Apr 26 16:43:33.613763 netatalk[11] {afp_avahi.c:94} (info:AFPDaemon): hostname: laysan
Apr 26 16:43:33.613786 netatalk[11] {afp_avahi.c:106} (info:AFPDaemon): Registering server 'laysan' with Bonjour

Since this Docker is built on Debian Jessie you can poke around in it by starting a shell if things don't look right,

docker exec -it timemachine /bin/bash

Update 2016

I used Tern for Timemachine backups for a few months. Go look at the page if you want details.

Update 2014

I built and used Netatalk 3 on Debian 6 but it turns out netatalk 2.2 works (in Debian 7). Since it is available in Debian 7 (aka Wheezy) you should upgrade your server and ignore the rest of this page!

Follow the instructions on this page instead: http://bullcreekstudio.com/uncategorized/debian-wheezy-mavericks-time-machine-server/

The outdated way

Build

Download source from http://sourceforge.net/projects/netatalk and build netatalk. Currently I am using 3.1.0

# install build prerequisites
sudo apt-get install build-essential libdb-dev
# download and unpack tar ball
# cd into source folder
./configure
make
sudo make install

Configure

Change the volumes to use extended attributes by editing /etc/fstab and add user_xattr to the options

This is my current afp.conf file

I used to start netatalk at boot by putting it in /etc/rc.local but then I installed the standard 2.2 package and removed it, and it left behind nice startup and config scripts that I recycled

apt-get install netatalk
apt-get remove netatalk

Edit /etc/init.d/netatalk Edit /etc/default/netatalk

bwilson@bellman:~$ cd /usr/local/etc
bwilson@bellman:/usr/local/etc$ cat afp.conf
;
; Netatalk 3.x configuration file
; manual: http://netatalk.sourceforge.net/3.0/htmldocs/

[Global]
log level = default:error
uam list = uams_guest.so uams_dhx.so
hosts allow = 192.168.123.108 192.168.123.109
vol preset = all_volumes
guest account = timemachine

[all_volumes]
file perm = 0664
directory perm = 0775
cnid scheme = dbd
valid users = julie bwilson

; [Homes]
; basedir regex = /home

[TimeMachine]
path = /green/timemachine
time machine = yes
valid users = timemachine