Troubleshooting Tip: Established call drops after 32 seconds

Description

This article describes what could have been the cause of the established call drops after 32 seconds.

Scope

FortiVoice.

Solution

1. The user is able to place a call; however, the call will drop exactly after 32 seconds of call establishment.

2. Perform a packet capture under System -> Network -> Traffic Capture.

3. Under the SIP connection, select the respective extension together with the dedicated utilized trunk, and select Capture All for Filter selection.
   
   

4. Based on the packet analysis 10.XX.XX.28 [Extension] ---> 10.XX.XX.88 [FortiVoice SIP Server] --> 208.XX.XX.140 [Trunk].
   

5. The FortiVoice 10.XX.XX.88 is waiting for an ACK packet from 10.XX.XX.28, hence the multiple resends of 200 OK.

6. Suggestion: check the connection between 10.XX.XX.28 [Extension] <---> 10.XX.XX.88 [FortiVoice SIP Server] to make sure the ACK packet is received.