Simple System Backup Tool

Reads sources from various configuration files and rsyncs them to a configurable target.

Programs

sysbackup

Main program. Performs the backup according to the configuration (see below).

sysbackup-create-ssh-keys

Creates a SSH key for the sysbackup user. With reasonable defaults. Any options are forwarded to ssh-keygen.

sysbackup-get-ssh-key

Displays contents of /var/lib/sysbackup/.ssh/id_ed25519.pub.

Dependencies

• rsync
• ssh-client for sysbackup-create-ssh-keys, sysbackup-get-ssh-key and to transfer data to SSH targets
• standard stuff: getopt, find, mkdir, mktemp

Configuration Files

/etc/sysbackup/backup.conf

Main configuration file. Specifies backup target ($TARGET) and other options. Unless the variable $BACKUP is set to true, calling sysbackup does nothing.

$TARGET might be any string accepted by rsync as destination, i.e., it could contain a remote SSH host, as in:

TARGET="[email protected]:backup/"

Additional options for rsync can be specified in $RSYNC_OPTIONS.

All source directories are searched for hidden marker files with the file name ".sysbackup-exclude". All directories containing such a marker file, are excluded from the backup. The marker file name can be configured via $EXCLUDEMARKER and accepts patterns as find -name. Setting $EXCLUDEMARKER to an empty value disables this feature.

See the provided and commented example configuration file for more information.

/etc/sysbackup/sources/

Directory with source files. Each file in this directory that ends in .list is interpreted as containing absolute source directories to be backed up. Empty lines and lines starting with a # are ignored.

Normally, each backup source is assigned a target name by replacing all / with _. If you want to assign another name, start the source line with Name=. All names must be globally unique.

The contents of the specified directory are transferred recursively. If you want to exclude certain directory (i.e., with large downloaded files), create an empty file .sysbackup-exclude in it.

/etc/sysbackup/scripts/

Directory with user-defined scripts. Prior to file transfer, each executable file $file in this directoy is run in the directory /var/lib/sysbackup/scripts/$file/ with stdout redirected to a file stdout in that directory. So, scripts in this directory can simply create files and/or write to stdout. The directory /var/lib/sysbackup/scripts is included by default in /etc/sysbackup/sources. If the scripts working directories do not exist, they are created before calling the scripts. They are not purged after running.

/var/lib/sysbackup/.ssh/id_25519.pub

Call sysbackup-create-ssh-key (as root) to create an SSH-Key for the sysbackup user. Call sysbackup-get-ssh-key to show the public key.

Environment Variables

SYSBACKUP_ROOT

All configuration files are resolved relative to SYSBACKUP_ROOT. Lines in the source files are unchanged.

Hooks

ToDo

Snapshot Management

Currently, there is no snapshot management included. See the wiki for configuration examples to get snapshots. Snapshots could be implemented with hooks.

Data Transfer

Upon invocation, sysbackup reads the configuration and source files. Then, it executes all scripts, as described above.

Then, the contents of each source directory $src are transferred using rsync to $TARGET/$src, where $TARGET is the configured target directory and $src is the name of the particular source directory.

By default, folling options are passed to rsync:

--archive --delete --delete-excluded --one-file-system
--compress --hard-links --inplace
--numeric-ids

You can override these default options by re-defining $RSYNC_OPTIONS_DEFAULT in the config file. If files matching the exclude marker (defaults to ".sysbackup-exlude") are found, the option "--exclude-from=" with an appropriate file is appended automatically. If verbose output is enabled, the options "--verbose --progress --human-readable" are appended. Finally, user-defined options in $RSYNC_OPTIONS are appended.

Normally, you should only need to set $RSYNC_OPTIONS in the configuration file, if at all.

Debian Package

Packaging files for Debian are on the branch debian. To build the package, use gbp(1) (available in Debian package git-buildpackage):

gbp buildpackage

Systemd Intergration

The Debian package ships with a systemd daemon and timer that runs the system backup daily at 5:43 in the morning. Override sysbackup.timer as you like.

The script is run as user sysbackup and so will the user defined scripts. In order to backup anything, this user must be able to call the requested commands and read the files to be backed up.