Time Capsule Setup (Debian Wheezy)

Time Machine, for all its faults, is an easy way to backup your Macintosh. For laptops that are used on the go, though, it is easy to forget to plug in your backup drive. Apple sells a wireless hard drive which lets you backup over the network, but it is way overpriced. Since you already have a server, why not just host it yourself?

It is actually pretty easy to do this. I followed (and modified) these instructions and these instructions for my purposes, and it worked just fine.

install netatalk 2.2+ aptitude install netatalk

Create user timemachine. This will be used to authenticate the computers. You can use an existing account, but segregation of authority is probably a good idea. If you are backing up multiple computers, you can either create different accounts or use the same one; either way it works. useradd -s /bin/false timemachine
passwd timemachine Make sure you include the /bin/false login shell, or else users could log into this account via a shell.

Create a folder which will host the backups. I like to separate each machine's backups from each other. Since I already have backup volumes for each machine (used for rsync backups, which I find to be more reliable than Time Machine), I can just create a folder in that volume. mkdir /mnt/backup/nova/timemachine
chown timemachine:timemachine timemachine/

Edit /etc/netatalk/AppleVolumes.default. Comment out the last line: #~/ "Home Directory" and add a line for each machine at the end of the file, pointing to the directory you just made: /mnt/backup/nova/timemachine "Nova Time Capsule" cnidscheme:dbd options:usedots,upriv,tm

Edit /etc/netatalk/afpd.conf. Add a line to the end of the file: - -tcp -noddp -uamlist uams_guest.so,uams_dhx.so,uams_dhx2.so -nosavepassword if the previous last line was not already commented out (it was for me), then comment it out now: #- -tcp -noddp -uamlist uams_dhx.so,uams_dhx2.so -nosavepassword

Restart netatalk /etc/init.d/netatalk restart

You should now see the newly created volume show up in your Time Machine Preferences when you select a backup drive. (The site I got this information from said you needed to add a system configuration change to see it, but that was not my experience, as of OSX 10.8.4 and 10.8.5). Just select the backup volume, enter the timemachine user and password you set earlier, (optionally) specify encryption, and the backup should start.

Update after months of use

For some reason the backups stopped working. Not sure why... in the process of troubleshooting I tried a few things, including verifying permissions on the backup volume (there were some .Apple* folders owned by root, which I changed to the timemachine user) and adding an empty file '.com.apple.timemachine.supported' in the root of the time machine volume. Not sure which of these did the trick, but it is back up and running now.