Using Dropbox as a Distributed Backup

A while back I made some improvements to the backup scheme we use at KaiNexus. The requirements were pretty simple and straight forward. All our backups had to be encrypted, offsite and distributed. While there are a number of for-pay backup solutions out there we were looking for the bare minimum and free solution.

At the office, we all use Dropbox for file sharing so it seemed like a logical tool to use since we were all familiar with it. Dropbox lets us check off two requirements by being both off site and distributed. Here’s my step-by-step guide on getting Dropbox setup on an Ubuntu server with minimal effort. I’m not covering the file encryption bit in this post but if you want to know how I did it let me know and I’ll do a writup on it.

The steps outlined here were put together after reading through a couple of other guides. Feel free to read those guides if you want but you should be able to get everything you need from what I have below.

Install Python

Install build-essentials and gcc

sudo apt-get install build-essential gcc

Download Python 2.5.5 (This seems to be the officially supported version)
```
wget http://www.python.org/ftp/python/2.5.5/Python-2.5.5.tgz
```
Extract
```
tar -xvzf Python-2.5.5.tgz
```

Compile and install

cd Python-2.5.5
./configure --prefix=/usr/local/python2.5
make
sudo make install
sudo ln -s /usr/local/python2.5/bin/python /usr/bin/python2.5

Install Dropbox

Switch to root user
```
sudo -s
```

Create dropbox user and group and set the user’s home to be** /etc/dropbox

groupadd dropbox
useradd -r -d /etc/dropbox -g dropbox -s /bin/false dropbox

Download the 64-bit Dropbox binary

wget -O /tmp/dropbox.tar.gz http://www.dropbox.com/download/?plat=lnx.x86_64

Create the dropbox user’s home and set the ownership and permissions

mkdir -p /usr/local/dropbox /etc/dropbox
chown dropbox.dropbox /etc/dropbox
chmod 700 /etc/dropbox

Extract the dropbox binaries

tar xvzf /tmp/dropbox.tar.gz -C /usr/local/dropbox --strip 1

Remove the dropbox archive
```
rm /tmp/dropbox.tar.gz
```
Switch to the dropbox user
```
su -l dropbox -s /bin/bash
```
Set the user’s permissions
```
umask 0027
```
Execute the dropbox daemon (Note: A URL will be repeated in the terminal window if the install machine is not registered to an account. Navigate to the URL (while logged in under the account you wish to link) and wait for the prompt to notify you that you are now linked. You’ll get a simple welcome message.)
```
    /usr/local/dropbox/dropboxd
```
Terminate the dropbox daemon with ctrl+c
Log out of the dropbox user
```
exit
```

Create the control script

cat >> EOF | sed -e "s,%,$,g" >/etc/init.d/dropbox
### BEGIN INIT INFO
# Provides:          dropbox
# Required-Start:    $local_fs
# Required-Stop:     $local_fs
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: starts the dropbox service
# Description:       starts dropbox using start-stop-daemon
### END INIT INFO

DROPBOX_USERS="dropbox"
DAEMON=/usr/local/dropbox/dropbox
unset DISPLAY

start() {
    echo "Starting dropbox..."
    for dbuser in %DROPBOX_USERS; do
        HOMEDIR=%(getent passwd %dbuser | cut -d: -f6)
        if [ -x %DAEMON ]; then
            HOME="%HOMEDIR" start-stop-daemon -b -o -c %dbuser -S -u %dbuser -x %DAEMON
        fi
    done
}

stop() {
    echo "Stopping dropbox..."
    for dbuser in %DROPBOX_USERS; do
        HOMEDIR=%(getent passwd %dbuser | cut -d: -f6)
        if [ -x %DAEMON ]; then
            start-stop-daemon -o -c %dbuser -K -u %dbuser -x %DAEMON
        fi
    done
}

status() {
    for dbuser in %DROPBOX_USERS; do
        dbpid=%(pgrep -u %dbuser dropbox)
        if [ -z %dbpid ] ; then
            echo "dropboxd for USER %dbuser: not running."
        else
            echo "dropboxd for USER %dbuser: running (pid %dbpid)"
        fi
    done
}


case "%1" in
  start)
    start
    sleep 1
    status
    ;;

  stop)
    stop
    sleep 1
    status
    ;;

  restart|reload|force-reload)
    stop
    start
    sleep 1
    status
    ;;

  status)
    status
    ;;

  *)
    echo "Usage: /etc/init.d/dropbox {start|stop|reload|force-reload|restart|status}"
    exit 1

esac

exit 0
EOF

Allow the control script to me executed and set it to autostart
```
chmod a+x /etc/init.d/dropbox
update-rc.d dropbox defaults
```
Start dropbox
```
/etc/init.d/dropbox start
```

You should now have Dropbox running as a service on your server. All that’s left is to create your cron jobs that run your backup scripts and have those backup files placed into the /etc/dropbox/Dropbox folder.

Menu

Install Python

Install Dropbox