Due to the number of end users who have Sonicwall Firewalls on their network, we here at FacetCorp have created this short guide demonstrating the configuration settings that we are aware of that can cause problems with SIP.
- Disable SIP Transformations.
- Enable Consistent NAT.
If these are not configured this way, you can experience the following problems:
- one-way audio with Remote Phones and SIP trunks.
- Remote phones that lose registration after a period of time.
- Remote phones that can make but not receive calls.