4 Replies Latest reply on Aug 11, 2010 11:49 PM by rcamm

    Port forwarding UDP packet issue (sip) - SG580 4.0.8

      On the weekend upgraded to the latest firmware on our SG580 as it had out of the blue stopped our satellite office from reaching one of our websites (customer service app).

      This seems to have resolved that but for some reason has now stopped our our Voip working between the offices.


      We use a trixbox pbx and using its diagnostics page it shows that it only receives 1 of 10 packets when testing any of the UDP ports. This had been working before although I did have a similar issue months back when setting this up originally but it started to work so not sure what if anything I may have done.


      I had, and now deleted and recreated the port forwarding rule again to see if that would help but still no go. In saying that an external VOIP provider we use seems to be registering onto the server so I'm guessing some of the UDP ports are getting through.


      I don't have rate limiting on nor see anything in the diagnostics pages being blocked.


      Has anyone had any issues with forward UDP ports on the SG's or any hints or suggestions. I don't think the config on this router has been cleared and re-entered since going from v3 to v4 so not sure if that could cause any issues, otherwise everything else has been fine.

        • 1. Re: Port forwarding UDP packet issue (sip) - SG580 4.0.8

          try disabling


          firewall -> connection tracking -> H323

          • 2. Re: Port forwarding UDP packet issue (sip) - SG580 4.0.8

            Hi Ross,

            Good to see you're still around. Remember getting your help on a SME575



            Sadly that didn't help. I actually had that off by default and then only turned it on the other day to try and fix this problem in the first place.


            It's weird as it apparently manages to get 1 of 10 packets out and then something stops the rest but just can't see anything in the local system log.


            I can see the 10 packets coming in as I have logging turned on for that rule but don't see anything going back out even though I have logging turned on for LAN -> Internet rule. Not sure if there is something extra to do to show these.

            • 3. Re: Port forwarding UDP packet issue (sip) - SG580 4.0.8

              you will need to use the packet analyzer to investigate further


              system -> diagnostics -> packet capture


              setup up a filter each for the WAN and LAN interfaces with options like


              -s 1500 ip a.b.c.d


              where a.b.c.d is the IP address of the external server you are trying to communicate with


              then reproduce the issue, stop the capture, and load into wireshark or inspect on the packet cature page.


              wireshark is good as it highlights bad packetsd in red usually.


              hope this helps.

              1 of 1 people found this helpful
              • 4. Re: Port forwarding UDP packet issue (sip) - SG580 4.0.8

                Hi Ross,

                Thanks, using that now to capture variations of packets to try and identify the ongoing issue. Got WireShark too so will open within there to see any major errors.