The host check command

You can refuse ICMP Ping requests and require a different schema for determining if a particular host is truly down. An example of a host that is functional, but is considered “Down” is illustrated as follows. The host “Backroom MOKEEFE” has a firewall rule that does not allow ICMP.

If you are running a server that is not allowed to respond to ping, consider alternatives. A baseline service provided is often a good choice. For instance, if you are running a web server, set the check-host-alive check to be a check-host-alive-http on the host.