VOIP Issues

How exactly did you disabled SIP ALG? Did you disabled or removed SIP session helpers as well?

Toshi

Hi ​@ethonkent ,

Use sniffer packet captures and logs to identify dropped packets or delays. If any DOS policy configured try to set status monitor and check the call status. 

Refer this below article provides a list of resources that can be used to configure and troubleshoot VoIP on FortiGate.
 

If you have found a solution, please like and mark it as solved to make it easily accessible for everyone.

Thanks,
Mayur Padma

Fairly new to Forti and deployed a range of 50G models at branch sites 5-10 users and HA pair of 70Gs at HQ which has been fine however, have an on going VOIP issue and looking for some guidance.

-Telephony platform is cloud hosted

-Disabled SIP ALG

-No VOIP profile applied to access rules

Issues raised:

-Calls dropping

-Audio being lost during calls

-Poor call quality  router login  

I got this,...

Hello ​@ethonkent ,

Disabling SIP-ALG is not the first Troubleshooting action to take.

Is the caller/User Agent registered to a PBX/Proxy?

Please conduct a packet capture on the FGT and check the session stats for SIP.

diag sys sip-proxy stats
diag sys sip-proxy stats clear
(call)
diag sys sip-proxy stats
>> check what is blocked

In the collected capture, review the SDP and RTP packets as per the below article,

If you have found a solution, please like and mark it as solved to make it easily accessible for everyone.