|A Cisco 7960G IP telephone (Photo credit: Wikipedia)|
Well, after being on the phone with Fortinet support for about three hours the other day my Systems Administrator and Fortinet tech support found out that it was the timeout setting in our traffic shaper for VoIP!
By default the session-ttl timeout is set for 150 seconds (2:30), which is why out calls were dropping out. We increased that number to 14400 (4 hours) and calls stopped dropping!
To configure that from the command line interface (cli) in FortiOS 5.2 run:
- config system session-ttl
- set default 14400