*Note:* There is no `default_system` variable!
+### [default_]backup_type
+
+Backup type to use. Default: `rsync`.
+
+- `rsync`: system backup using rsync(1).
+ Use `source_root` to specify the root directory to save.
+
+- `scp`: file backup using scp(1).
+ Use `files` to specify the files to copy.
+
+Please note that neither `ssh_args_add`, `rsync_args_add`, `compress`, nor any
+"exclude" parameters are supported when using the "scp" backup type! And There
+"scp" backup type never _deletes_ files from the backup store; so if you reduce
+the list of files to backup, old files will still be kept, because they were
+already saved in an older generation (but no longer updated).
+
### [default_]user
Remote user. Default: `root`.
When saving the whole (remote) system ("/"), default excludes are set up
automatically, which exclude standard system directories like /sys and /proc.
+### [default_]file
+
+Space separated list of files to copy when using the "scp" `backup_type`.
+Default: "running-config".
+
### [default_]target
Local backup directory. The backup of each system is stored in a folder named
### [default_]compress
-Enable (1) or disable (0) compression. Default: 1 (on).
+Enable (1) or disable (0) rsync transfer compression. Default: 1 (on).
### [default_]ping