Backup - Docker Container

This container is used to backup your data to a restic repository.

Usage

Pull the docker image from the GitHub Container Registry

docker pull ghcr.io/valentin-kaiser/backup:latest

Run the container with the following command or use docker compose

docker run -d \
    --name backup \
    -v /path/to/your/source:/source \
    -v /path/to/your/backup:/backup \
    -v /path/to/your/password:/run/secrets/backup_password \
    ghcr.io/valentin-kaiser/backup:latest

Volumes and secrets

• /source: The source directory to backup
• /backup: The target directory to backup to a restic local repository
• /run/secrets/backup_password: The password file for the restic repository

Configuration via environment variables

The container schedules the backup and forget scripts using cron. Your data should be mounted to /source and your backup to /backup, but Restic can backup to different types of repositories. Possible values are local, sftp, rest, s3, gs, b2, azure, rclone. Per default the container uses a local repository. You should mount the repository to /backup or configure it using environment variables. To secure your backup you should use docker secrets/a password file. The password file should be mounted to /run/secrets/backup_password.

You can fine tune restic and the backup and forget commands using the following environment variables and restic environment variables.

• BACKUP_SCHEDULE: The schedule for the backup. Default: 0 0 * * *
• FORGET_SCHEDULE: The schedule for the forget command. Default: 0 0 * * *
• RESTIC_SOURCE: The source directory to backup. Default: /source
• RESTIC_REPOSITORY: The backup repository. Default local directory: /backup
• RESTIC_PASSWORD_FILE: The password file for the restic repository. Default: /run/secrets/backup_password
• RESTIC_BACKUP_ARGS: The arguments for the backup command. Default: --exclude-caches --exclude-if-present=.nobackup --exclude-file=/.backupignore
• RESTIC_FORGET_ARGS: The arguments for the forget command. Default: --prune --keep-daily 7 --keep-weekly 4 --keep-monthly 6
• RESTIC_COMMPRESSION: The compression algorithm to use. Default: auto

Ensure target is mounted

• MOUNT_LOCK_TEST: Whether to check if the target is mounted. Default: true
• MOUNT_LOCK_FILE: The file to check for. Default: /.mounted

Scripts

The container ships with four scripts:

• /entrypoint.sh: The entrypoint script ensures that the restic repository is initialized and the cron job is scheduled and daemon started
• /backup.sh: The backup script runs the restic backup command and will be scheduled by cron to create new backups
• /forget.sh: The forget script runs the restic forget command and will be scheduled by cron to prune old backups
• /restore.sh: The restore script leads you through the restore process

Logging

The container logs to three different log files that can be found in /var/log:

• /var/log/backup.log: The output of the backup command
• /var/log/forget.log: The output of the forget command