*RSnapshot* is an efficient incremental backup system running over SSH.
*RSnapshot* makes very efficient backups in trees (each of which look exactly like the tree being backed up) by prolific use of *symlinks*.
By default, *RSnapshot* groups backup sub-trees under
alpha.0 (daily or more frequent) alpha.1 : beta.0 (weekly or more frequently) beta.1 : gamma.0 (monthly or more frequently) gamma.1 : delta.0 (etc.) delta.1 :
The backup policy can be configured very flexibly (by configuration of *crontab* entries).
On *Debian* and *Ubuntu* derivatives the simplest way to install it is to run
sudo apt install rsnapshot
and on _OpenBSD_ to run
sudo pkg_add rsnapshot or
doas pkg_add rsnapshot
on the command line. This will ensure that *rsync* and *ssh* are installed as well.
The quickest and easiest way to configure it (including the *cron* tasks) is to install Webmin and enable the *RSnapshot* plugin. This will set up sensible defaults.