SS_FPING showing 55-65% Packet Loss instead of 100(UDP PING)

[dllivipuma]

Hello,

I installed the Advanced Ping 1.3 template and everything works fine with ICMP. But with UDP I have troubles.
I created a Graph for a DNS Server. I specified the protocol to be UDP and the port to be 53. When the service is "running", the graph shows everything correct, but when I stop the service, the graph shows only 55-65% packet loss (it should be 100% because the service isnt running).

I've tested the ss_fping with a Router (which is not running a DNS service) and it also shows that the packet loss is 55%-65%. I've modified the script so it shows the Ping Status (the time it takes to respond) and the Ping Response:

[root@gye scripts]# php -q ss_fping.php 1.1.1.1 10 UDP 53
2.39 UDP Ping Success (2.39 ms)
down UDP ping Timed out
down UDP ping Timed out
1.18 UDP Ping Success (1.18 ms)
down UDP ping Timed out
down UDP ping Timed out
2.18 UDP Ping Success (2.18 ms)
down UDP ping Timed out
down UDP ping Timed out
1.09 UDP Ping Success (1.09 ms)
min:1.0900 avg:1.7100 max:2.3900 dev:0.5806 loss:60.0000

However, when I run a tcpdump, it doesnt show any response from the Router. It only shows the 10 packets that the Cacti is sending to the device.

What could be the issue? I also ran a test to the UDP port 54 and it showed the same thing.

The Cacti Version Im using is the 0.8.7g

Please help me!

Im attaching the ss_fping and ping files

[dllivipuma]

Any ideas?