Another example of how to use the EtherCard library:
This example illustrates doing DHCP, DNS, and then periodically pinging a remote server to see if it’s alive.
Sample output:
As you can see, it not only pings others, but also reports when it’s being pinged by others.
Add a LED and you could make a trivial server status display. Or add a web page fetch to verify that the web server is also still alive. Or add a graphics display to show a graph of the ping times. Or add a relay and power-cycle the server when it’s not responding … endless possibilities, and very simple to implement!