Problems with Gamma SIP trunks with SonicWall Gen7 firewalls when running older PBXs
Problem
You've just deployed a new SonicWall Gen 7 firewall or upgraded the firmware (7.0.1.x) on a Gen 7 firewall and started to experience VoIP problems between a phone system (PBX) and Gamma (SIP).
Answer
Firstly, make sure all the standard correct settings are complete. Full details here.
However, if it was working previously and you're running an older PBX, it is likely to be a bug brought in the 7.0.1.x firmware and related to Issue ID GEN7-26633. The only answer is to upgrade to 7.1.1 firmware which should resolve the problem. Please be aware that 7.1.1 is a big release so plan any updates and keep copies of the settings before and after the upgrade so you can go back if any other problems.
7.1 firmware release notes: SonicOS 7.1 Release Notes
Environment
Hardware: Gen 7 firewall including TZ270, TZ370, TZ470, TZ570, TZ670, NSa 2700, NSa 3700, NSa 4700, NSa 5700, NSa 6700
Firmware: Gen 7 including 7.0.1.x
