In this article, we will learn how to backup our data. We will take advantages of Scaleway’s Object Storage service and Duplicity. Duplicity is a free and open-source tool that backs up folders to a remote server. Using libsync and GPG, Duplicity is able to make space-efficient encrypted backups.
Our objectives are to:
To achieve this, we will:
You can easily backup your existing dedicated server with Duplicity. When you are using a Online by Scaleway Dedibox or a Scaleway Bare Metal Server, the data transfer is free of charge within the same region.
Requirements
- You have access to a Ubuntu/Debian server
- You have an account and are logged into console.scaleway.com
- You have generated your API Token
1 . Log in to the Scaleway Console
2 . Click Storage from the left side menu. The Storage page lists all your buckets. At first, your list is empty as you have not created any bucket yet.
3 . Click Create a Bucket to create a bucket that will store your objects.
4 . Name your bucket and validate your bucket creation. A bucket name must be unique and contain only alphanumeric and lowercase characters.
We are going to install Duplicity. To make sure we can generate a GPG Key, we need to create some entropy, we suggest using Haveged constantly on your sever to generate a small amount of entropy.
For Ubuntu and Debian :
apt-get install software-properties-common
add-apt-repository ppa:duplicity-team/ppa
apt-get update
apt-get install -y duplicity python-boto
apt-get install -y haveged
update-rc.d haveged defaults
The instructions that follows will also work for CentOS / RHEL / Fedora and MacOS
To generate the GPG key, launch this command.
gpg --full-generate-key
Enter and remember a passphrase. You will be asked to define the characteristics of your keys. We will go with default settings:
GPG will then ask how to call your key, an address and a description.
$ gpg --full-generate-key
gpg (GnuPG) 2.1.18; Copyright (C) 2017 Free Software Foundation, Inc.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Please select what kind of key you want:
(1) RSA and RSA (default)
(2) DSA and Elgamal
(3) DSA (sign only)
(4) RSA (sign only)
Your selection? 1
RSA keys may be between 1024 and 4096 bits long.
What keysize do you want? (3072) 3072
Requested keysize is 3072 bits
Please specify how long the key should be valid.
0 = key does not expire
<n> = key expires in n days
<n>w = key expires in n weeks
<n>m = key expires in n months
<n>y = key expires in n years
Key is valid for? (0) 0
Key does not expire at all
Is this correct? (y/N) y
GnuPG needs to construct a user ID to identify your key.
Real name: backups
Email address: me@scaleway.com
Comment: Scaleway Object Storage backups
You selected this USER-ID:
backups (Scaleway Object Storage backups) <me@scaleway.com>
Change (N)ame, (C)omment, (E)mail or (O)kay/(Q)uit? O
We need to generate a lot of random bytes. It is a good idea to perform
some other action (type on the keyboard, move the mouse, utilize the
disks) during the prime generation; this gives the random number
generator a better chance to gain enough entropy.
gpg: key XXXXXXXXXXXXXXXX marked as ultimately trusted
public and secret key created and signed.
pub rsa3072 2019-11-05 [SC]
XXXXXXXXXXXXX-FINGERPRINT-XXXXXXXXXXXXXX
uid backups (Scaleway Object Storage backups) <me@scaleway.com>
sub rsa3072 2019-11-05 [E]
You will need to use the GPG Key fingerprint, it could be an 8, 16 or 40 char long hash. You can also find the fingerprint of your key with the command :
$ gpg --list-keys
gpg: checking the trustdb
gpg: marginals needed: 3 completes needed: 1 trust model: pgp
gpg: depth: 0 valid: 1 signed: 0 trust: 0-, 0q, 0n, 0m, 0f, 1u
gpg: next trustdb check due at 2020-11-13
/home/me/.gnupg/pubring.kbx
------------------------------
pub rsa3072 2019-11-05 [SC]
XXXXXXXXXXXXX-FINGERPRINT-XXXXXXXXXXXXXX
uid [ultimate] backups (Scaleway Object Storage backups) <me@scaleway.com>
sub rsa3072 2019-11-05 [E]
If you lose access to your current server, having the GPG private and public keys stored somewhere else will come in handy. Export the GPG keys with:
gpg --armor --export backups
gpg --armor --export-private-key backups
Everything is installed and ready, we will now configure and script our interactions between our server and the cloud.
1 . Create our initial scripts files, and our log files.
touch scw-backups.sh scw-restore.sh .scw-configrc
chmod 700 scw-backups.sh scw-restore.sh
chmod 600 .scw-configrc
mkdir -p /var/log/duplicity
touch /var/log/duplicity/logfile{.log,-recent.log}
2 . Add the following lines to .scw-configrc :
# Scaleway credentials token
export AWS_ACCESS_KEY_ID="<SCALEWAY ACCESS TOKEN>"
export AWS_SECRET_ACCESS_KEY="<SCALEWAY SECRET ACCESS TOKEN>"
export SCW_BUCKET="s3://s3.nl-ams.scw.cloud/<NAME OF YOUR BUCKET>"
# GPG Key information
export PASSPHRASE="<YOUR GPG KEY PASSPHRASE>"
export GPG_FINGERPRINT="<YOUR GPG KEY FINGERPRINT>"
# Folder to backup
export SOURCE="<PATH TO FOLDER TO BACKUP>"
# Will keep backup up to 1 month
export KEEP_BACKUP_TIME="1M"
# Will make a full backup every 10 days
export FULL_BACKUP_TIME="10D"
# Log files
export LOGFILE_RECENT="/var/log/duplicity/logfile-recent.log"
export LOGFILE="/var/log/duplicity/logfile.log"
log () {
date=`date +%Y-%m-%d`
hour=`date +%H:%M:%S`
echo "$date $hour $*" >> ${LOGFILE_RECENT}
}
export -f log
Our current backup policy is to make a full backup every 10 days and remove all backups older than one month.
Using the configuration and duplicity, we will automate the backups. Add the following lines to scw-backup.sh:
#!/bin/bash
source <FULL PATH TO>/.scw-configrc
currently_backuping=$(ps -ef | grep duplicity | grep python | wc -l)
if [ $currently_backuping -eq 0 ]; then
# Clear the recent log file
cat /dev/null > ${LOGFILE_RECENT}
log ">>> removing old backups"
duplicity remove-older-than ${KEEP_BACKUP_TIME} ${SCW_BUCKET} >> ${LOGFILE_RECENT} 2>&1
log ">>> creating and uploading backup"
duplicity \
incr --full-if-older-than ${FULL_BACKUP_TIME} \
--asynchronous-upload \
--encrypt-key=${GPG_FINGERPRINT} \
--sign-key=${GPG_FINGERPRINT} \
${SOURCE} ${SCW_BUCKET} >> ${LOGFILE_RECENT} 2>&1
cat ${LOGFILE_RECENT} >> ${LOGFILE}
fi
Let’s test the script. Run the script ./scw-backups.sh to make sure the configuration is correctly set. Check Scaleway’s bucket on the web interface and the logs with :
cat /var/log/duplicity/logfile-recent.log
The other duty of duplicity is to recover a backup, we will create a script to make the process easier. In scw-restore.sh, add the following:
#!/bin/bash
source <FULL PATH TO>/.scw-configrc
if [ $# -lt 2 ]; then
echo -e "Usage $0 <time or delta> [file to restore] <restore to>
Exemple:
\t$ $0 2018-7-21 recovery/ ## recovers * from closest backup to date
\t$ $0 0D secret data/ ## recovers most recent file nammed 'secret'";
exit; fi
if [ $# -eq 2 ]; then
duplicity \
--time $1 \
${SCW_BUCKET} $2
fi
if [ $# -eq 3 ]; then
duplicity \
--time $1 \
--file-to-restore $2 \
${SCW_BUCKET} $3
fi
Let’s try recover the data you uploaded in the previous section:
./scw-restore.sh 0D /tmp/backup-recovery-test/
You can also recover one specific file with the following format from a backup 5 days ago with:
./scw-restore.sh 5D <file> /tmp/backup-recovery-test/
Use this command crontab -e to edit your crontab file and add the line to create a script that will run twice a day at 1:00 and 13:00 (1 AM and 1 PM) :
crontab -e
And after selection your editor, write down :
00 1,13 * * * <FULL PATH TO>/scw-backup.sh > /dev/null 2>&1
We manage to create an automatic backup using Duplicity, hosting encrypted data on Scaleway’s Object Storage. We are able to recover specific files or the entire backup itself at a given date.
To continue your implementation, you may want to consider the following:
“SOURCE=/” and the --include= and --exclude= options of duplicity.