added cron task

README.md

@@ -1,5 +1,14 @@
-# scripts
+# srv-scripts
 
 Execute `sync.sh` to copy scripts on the server.
 
+> 
 > `vol-restore` is not yet finished !
+
+## Cron
+
+Add this line into the host crontab with `crontab -e`.
+```
+# Backup volumes every days at 4am
+0 4 * * * /usr/local/bin/vol-backup-all
+```