Recursive DNS server reachability alarm/alert

Do to the critical nature of DNS to most applications of an organization and the requirement for Tapestry to put a new device in-line to the recursive DNS servers, Tapestry should constantly monitor DNS service reachability (e.g. ICMP to the configured recursive DNS servers) and trip an alarm and send text/email alerts to Tapestry operators if reachability seems to be compromised.
