Best posts made by whoolly

Thanks everyone, after getting the vendor all of Digium's sonic wall reference, they made all the changes and things so far appear to be back to normal.

Apparently spoke too soon.
The vendor providing the Sonicwall and the client are now saying same issues again.
You will call from one extension to another and it will ring twice and go to VM.
Sometimes this happens a couple of times before the call will go through.
firewall provider says that they have made all of the switchvox recommended settings.
So any other ideas?
I will try to coordinate a call between Switchvox support and the Sonicwall provider.

They told me that they changed it to 3600 instead of 30s.
They also said that Sonicwall told them that they had to have a NAT statement to translate my phone servers public IP into something on their network, so they are translating it to the IP of on of their switches.
That doesn't make any sense to me at all.
I have a little meraki firewall that we use for a spare cable modem connection, i put 2 phones onto that and registered the phones and have not had any issues.

Client will not replace the Sonicwall and insists that they do this all the time and never have any voip issues with Sonicwall. They now want to do a L2L VPN tunnel for the voice network back to the internal IP of our PBX. I would rather not do this, but the boss wants the issue resolved.
As I said before, they are trying to do a NAT of my public IP of my PBX to the internal IP of one of their layer 2 switches .. why ... I dunno.
I am no network guru in any stretch, but this doesn't seem right at all.
see below quote from client and sonic wall

"Spoke with another Sonicwall support engineer regarding Sonicwall ticket #42488945, the VoIP phone system issue. The Sonicwall engineer noted that when traffic is initiated by the external PBX (SwitchVOX at SC Boro) the destination port is a random port number anywhere in the 10,000’s range. The Sonicwall, as it is currently configured, properly allows and forwards this traffic to the Internal SCboro Gateway which is one of the Cisco SF300 switches at 10.1.8.6. This switch does not know where to forward the traffic for this destination port. The Sonicwall engineer stated that there would have to be an internal voice server that could interpret the destination ports and forward the voice traffic to the appropriate VoIP phone, or the external SwitchVOX would have to bind the destination ports with the VoIP phone extensions."

Do you have any suggestions on where to go next?

we ended up going the route of the L2L VPN to get the phones to work. Vendor insisted he has never had any VOIP issues with Sonicwall and didn't want to budge on that. After a day of them figuring out how to put the phones on a separate Vlan and then getting that traffic to the firewall, we finally got the vpn up and working and the phones registered again. All in all a very frustrating experience, thanks to everyone here for the help.
If only we could charge by the hour, but we don't as we are one gov agency helping another.
If anyone else here besides SAM will be in Austin later this year, see you at Touche's.