Having issues with calls dropping for no reason on a new SIP trunk customer.
MBG is setup as the trunk gateway, but is in custom mode behind a SonicWall firewall. IT department has told me that they have completely turned off the SIP aware fields on the SonicWall.
However, the carrier is sending a OPTIONS message every 60 seconds as a keep alive. The MBG sees that message come in on 5060. But when it goes to reply, it replies on port 14793.
I've never seen this before and am unsure if the pcap taken from the MBG is actually showing the MBG sending on 14793 or somehow showing that the SonicWall has changed it to 14793.
Can anyone offer any help or suggestions? Mitel support seems pretty befuddled about this as well.