Capability to check UDP's ports, for services with just an udp port
For some services we have only a UDP port to check, just tcp is aviable at this moment.
Indeed that's an idea but unfortunately there's no notion of "connection" for UDP so it's not possible to know if a port is filtered or if a service is simply not responding because it waits for a specific message for example. There is just one obvious case when the port is "officially" closed and so a response is sent to tell you that. Which kind of service would you like to monitor? would it require to send a specific packet? would it need to check for a response? Is just knowing that no response is received (not knowing if it's filtered or open) enough for your use-case?
Olivier Mary commented
Somes games servers have all port only udp