Hi,Traditionally, ICMP echo requests and ICMP echo responses are used for ping testing, and this is done under the ICMP protocol. I've never seen a UDP ping test before. "Validate reply" cannot be treated as a UDP ping function. [URL]  If you want to see each host's UDP connections, you can use an analyzer or for example with the "netstat -n" command in Windows to server-side. Hope it helps!
Does your DELL switch have UDP Ping?