I’m slowly integrating an Asterisk system into an Iwatsu ECS system over SIP extensions (to and from Iwatsu). Most of it is working except for a small hang up problem. The system is is connected PSTN <–> Iwatsu <–> Asterisk. Both Iwatsu and Asterisk have phones connected to them and I can dial extensions between the two systems. After hanging up on a phone on the Asterisk end the Iwatsu end doesn’t get a hang up signal and just holds the line forever this can be either from calling an extension or calling an outside line through Iwatsu. Any ideas?
Your best bet is to debug the SIP session, you should see a BYE from Asterisk when the call hangs up. It is most likely a problem with your other PBX if Asterisk is sending the correct SIP messages.