Thanks in advance for any suggestions on this one!
The issue we are having is the dial by extension feature between the Main Site to Remote Site 5. Some extensions (not all extensions) from Remote Site 5 can dial some (not all extensions) Main site extensions and vice versa. I disabled sip-helper and sip-nat-trace in both the 100D and 60D in both sides. I also deleted the SIP session helper from both devices. Both changes made no difference.
Dial by Extension works fine between Main Site and Remote Sites 1,2 and 3.
I have opened a ticket with Fortinet TAC, but they are only confirming that that I appear to have everything setup correctly and no port blocking or monitoring is stopping any traffic.
This was working previously with a Watchguard at the main site and an ASA5505 as the Remote Site 5. There were no references to SIP management in either of those devices.
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