docker-backup-duplicity

Backup solution for Docker volumes based on Duplicity

Usage

Note

: The following instructions assume Google Drive is used as a storage backend; refer to duplicity's man page to find out how to configure different backends!

1. Create a new volume in Docker with the name duplicity_credentials:

   # docker volume create duplicity_credentials
   

2. Create a new file in the host system with the name /root/secrets/backup/passphrase.txt, and enter in it a secure passphrase to use to encrypt files:

   # echo 'CorrectHorseBatteryStaple' >> /root/secrets/backup/passphrase.txt
   

3. Obtain Desktop Application OAuth credentials from the Google Cloud Console.

4. Create a new file in the host system with the name /root/secrets/backup/client_config.yml, and enter the following content in it:

   # edit /root/secrets/backup/client_config.yml
   

   client_config_backend: settings
   client_config:
       client_id: "YOUR_GOOGLE_CLIENT_ID_GOES_HERE"
       client_secret: "YOUR_GOOGLE_CLIENT_SECRET_GOES_HERE"
   save_credentials: True
   save_credentials_backend: file
   save_credentials_file: "/var/lib/duplicity/credentials"
   get_refresh_token: True
   

5. Add the following keys to the docker-compose.yml file of the project you want to backup:

   # edit ./docker-compose.yml
   

   1. If you haven't already, upgrade your docker-compose.yml file to version 3.9:

      version: "3.9"
      

   2. Connect the previously created duplicity_credentials volume to the project:

      volumes:
          duplicity_credentials:
              external: true
      

   3. Setup the two previously created files as Docker secrets:

      secrets:
          duplicity_passphrase:
              file: "/root/secrets/backup/passphrase.txt"
          google_client_config:
              file: "/root/secrets/backup/client_config.yml"
      

   4. Add the following service:

      services:
          backup:
              image: "ghcr.io/steffo99/backup-duplicity:latest"
              restart: unless-stopped
              secrets:
                  - google_client_config
                  - duplicity_passphrase
              volumes:
                  - "duplicity_credentials:/var/lib/duplicity" 
                  # Mount whatever you want to backup in subdirectories of /mnt
                  - ".:/mnt/compose"  # Backup the current directory?
                  - "data:/mnt/data"  # Backup a named volume?
              environment:
                  MODE: "backup"  # Change this to "restore" to restore the latest backup
                  DUPLICITY_TARGET_URL: "pydrive://YOUR_GOOGLE_CLIENT_ID_GOES_HERE/Duplicity/this"  # Change this to the Drive directory you want to backup files to https://man.archlinux.org/man/duplicity.1.en#URL_FORMAT
                  # Don't touch these, they allow the program to read the secrets
                  DUPLICITY_PASSPHRASE_FILE: "/run/secrets/duplicity_passphrase"
                  GOOGLE_DRIVE_SETTINGS: "/run/secrets/google_client_config"
      

6. Log in to Google Drive and perform an initial backup with:

   # docker compose run -i backup --entrypoint=/bin/sh /etc/periodic/daily/backup.sh
   

7. Properly start the container with:

   # docker compose up -d && docker compose logs -f