I need to come up with a shell script that will launch another script when a specific host is detected on the network. This is for an network backup system. The host is always off-line when the back up runs at the night and I want to fire the backup off when it comes back on-line. The script would run on the backup server as a cron job, and needs to call the backup script only once per day. The backup server is Linux. The host is Windows XP.