Modified backup-files to not rely on a script.

backup-files-rsync.service

@@ -0,0 +1,12 @@
+[Unit]
+Description=Backup Files
+
+[Service]
+Environment=SOURCE=/path/to/source
+Environment=DESTINATION=user@host:/path/to/destination
+Environment=EXCLUDES="--exclude path1 --exclude path2"
+Type=simple
+Nice=19
+IOSchedulingClass=2
+IOSchedulingPriority=7
+ExecStart=/bin/sh -c '/usr/bin/rsync -HAax ${EXCLUDES} "${SOURCE}/" "${DESTINATION}/"'

backup-files-rsync.timer

@@ -0,0 +1,10 @@
+[Unit]
+Description=Backup Files
+
+[Timer]
+OnCalendar=04:15:00
+AccuracySec=300s
+Persistent=true
+
+[Install]
+WantedBy=timers.target