A SHORT INTRODUCTION TO DUPLICITY WITH CLOUD OBJECT STORAGE. Version

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1. INTRODUCTION

Welcome to Cloud&Heat! The purpose of this document is to show you how to use the Duplicity software in combination with Cloud Object Storage .

Duplicity is free software available under the GNU General Public License (GPL) and provides encrypted remote backups of files and directories . We will provide you with a backup script and walk you though how to set it up to perform a backup on a regular basis .

Duplicity works best on an all Unix-like system like Linux and MacOSX, but can also be used to backup Windows systems under Cygwin . Duplicity supports deleted files, Unix permissions, directories and symbolic links .

The steps we will go though are the following:

1) System configuration (Section 2) . 2) Create backup script (Section 3) . 3) Setup periodic backups (Section 4) .

In Section 5, we also show how to restore the files that were backed up .

The backup script runs on all systems where python-2, duplicity-0 .6 .22 and python-swift client are installed . Instructions on how to make your system meet these requirements are included in Section 2 . The instructions in this document have been tested with Ubuntu 12 .04 and 13 .10 with the Desktop and Server alternatives, res-pectively .

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2. SYSTEM CONFIGURATION

The steps we need to perform to setup the system that should be backed up are as follows:

1) Log in to the machine that you want to backup . This could be your local computer or a VM running in the Cloud . For instructions on how to log in to a Cloud&Heat VM, please see A Short Introduction to Cloud Compute .

2) Make sure the system is up-to-date:

sudo apt-get update sudo apt-get -y upgrade

3) In order to get the newest version of Duplicity, we now add an external repository .

sudo add-apt-repository -y ppa:duplicity-team/ppa

4) On Ubuntu 12 .04 we also need to execute

sudo add-apt-repository -y cloud-archive:havana

Note: On Ubuntu you can find out which version you have by executing the following command:

lsb_ release -a

5) Then we install the necessary programs:

sudo apt-get update

sudo apt-get install -y duplicity python-swiftclient anacron

6) Verify that the correct version of Duplicity was installed - at least 0 .6 .22 is required .

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3. CREATE BACKUP SCRIPT

We will now create the backup script itself. In this example we name the file backup_home.py, assuming we want to backup the home directories located in /home.

1) Create a directory for the backup script:

sudo mkdir -p /usr/local/bin

2) Download the backup script template from the Cloud&Heat Dashboard under Access & Security  API Access  Download Duplicity Script . See A Short Introduction to Cloud Compute for instructions on how to log in to the Cloud&Heat Dashboard . Save the template as /usr/local/bin/backup_ home.py.

3) Modify the backup script template by setting the values for all variables starting and ending with @@ . The values for all these variables should be chosen according to the following guidelines:

@@DASHBOARD _ PASSWORD@@:

This the password used to log in to the Cloud&Heat Dashboard .

Warning: If the password contains the character ‚, it has to be preceded by a backslash (\) .

@@PASSWORD _ BACKUP@@:

Password used to symmetrically encrypt the backup .

Warning: If the password contains the character ‚, it has to be preceded by a backslash (\) .

@@CONTAINER _ NAME@@:

The name of the container in which the backup should be stored in the Cloud . The name can only contain the characters a-z, A-Z, 0-9 or - . The container may already exist and will be accessible under the Containers tab in the Cloud&Heat Dashboard . See A Short Introduction to Cloud Object Storage

for instructions on how to access it .

@@BACKUP _ DIRECTORY@@:

Path of the directory to be backed up, e .g ., /home .

@@BACKUP _ EXCEPTIONS@@:

A list of absolute paths of directories within _{@@BACKUP _ DIRECTORY@@} that should not be backed up . Multiple entries are possible and given in a (possibly empty) list . For example, if the directories @@ BACKUP _ DIRECTORY@@/paul and @@BACKUP _ DIRECTORY@@/anja/Downloads should be exclu-ded from the backup, the variable @@BACKUP _ EXCEPTIONS@@ in the backup script, should be repla-ced by the following:

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sudo chmod 700 /usr/local/bin/backup_home.py

5) To check that the script works one can now run it using:

sudo /usr/local/bin/backup_ home.py

It should exit without errors . To verify that the backup was stored in the Cloud Object Storage, log in to the Cloud&Heat Dashboard (see A Short Introduction to Cloud Compute for instructions) and go to the Containers tab in the side bar on the left . Here you should see a container with the name you chose (the _{@@CONTAINER _}

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4. SETUP PERIODIC BACKUPS

To automatically perform the backup on a regular basis, we recommend using the program anacron. It is already installed, so all we need to do is the following:

Create a symbolic link with the following command:

sudo ln -s /usr/local/bin/backup_ home.py /etc/cron.daily/backup_home

Note that the name of the link in /etc/cron.daily cannot contain the “ .“ character, and thus we call it back-up _ home instead of backup _ home.py .

Apart for the directory cron.daily (used for daily backups) the directories cron.hourly, cron.monthly

and cron.weekly also exist . See the man page for anacron for more information .

Note: The files in the cron directories must have names that only consist of the following characters: Capital and lower case letters (A-Za-z), digits (0-9), underscores (_) and dashes (-) . Otherwise they will not be execu-ted .

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5. RESTORE FILES

To restore the backup, the following command can be used (the values to use for the variables are described below):

SWIFT _ USERNAME=“OS _ PROJECT _ NAME:OS _ USERNAME“ \ SWIFT _ AUTHURL=“OS _ AUTH _ URL“ \

SWIFT _ AUTHVERSION=2 \

SWIFT _ PASSWORD=“@@CLOUDANDHEAT _ DASHBOARD _ PASSWORD@@“ \ duplicity swift://@@CONTAINER _ NAME@@ @@TARGET _ DIRECTORY@@

The @@ variables, must all be set to the same values as they had in the backup script that performed the backup (see Section 3) . _{@@TARGET _ DIRECTORY@@} should be the name of the directory where the backup should be restored . Directories that were excluded when performing the backup will not be created .

To find the values for variables starting with OS_, download the RC file from the Cloud&Heat Dashboard under

Access & Security  API Access  Download OpenStack RC File .

After executing the command you will be asked for a passphrase . This is the _{@@PASSWORD _ BACKUP@@} that was used in the backup script .