I'm a little stumped right now. We recently had a new NEC SV8100 installed along with all the internal hard phones, internal SIP clients (UC Desktop Suite) and external DT700's.
Everything is working except. Every 30minutes the external DT700's lose their connection, jump to a network busy message and then reconnect after they finish their reboot.
It appears to be linked to the keep-alive timeout period of the DT700's but I cannot seem to locate the right setting to resolve the issue.
On my pfSense firewall, I have the outbound NAT set to static port mapping. I have the inbound rules in place for UDP (5080 - 5081 & 10020 - 10083). I had originally set the Firewall Optimizations Options to Conservative under System -> Advanced -> Firewall and NAT, but "Normal" seems to work the same way. I changed it when I read on the pfSense forums that you should change the keep-alive time on the SIP configuration.
With that in mind I jumped on my SV8100 and set the H.323/SIP Phone KeepAlive Setup options:
84-15-02 [KeepAlive Message Interval] = 1
84-15-03 [KeepAlive Message Timeout] = 10
84-15-04 [KeepAlive Timeout] = 5
And applied them. Unfortunately, these did not seem to help the problem. So then I figured, well let me configure my traffic shaping to prioritize VoIP packets. Again no dice.
What am I missing. I've been searching high and low for answers. But I feel that I'm starting to get muddled under a bunch of settings that after changing them, I may end up finding the answer but not knowing how the issue was resolved. As, it stands, the keep alive settings are currently as specified and the traffic shaping is still enabled. The only other setting that I have changed on the NEC SV8100 is 10-12-06 NAPT Router - Enabled.
Thanks for any assistance.