firewall checker

[Qassem]

after I run the firewall checker I have a problem with this service
1- testing 3CX PhoneSystem 01 SIP Server... failed
2- detecting SIP ALG... failed

But i already disabled sip alg from the firewall (FortiGate)

set sip-expectation disable
set sip-nat-trace disable
set default-voip-alg-mode kernel-helper-based

and rebooted the firewall

 

[NicholasP_3CX]

Check the ISP router as well. This might also have SIP ALG enabled.

 

[Qassem]

Could you check the ISP router as well? This might also have SIP ALG enabled.

the main problem the incoming calls drop after 30 seconds
with twilio
SIP ALG is it related to the problem?

 

[NicholasP_3CX]

Definitely would be related to this. SIP ALG interferes with the communications, and that would cause the disconnection.

For the firewall checker to give a result like this, it means SIP ALG is enabled somewhere on the network, either on your firewall, or on the ISPs router.

 

[Alex Renard]

Try checking your firewall rules to make sure SIP and RTP ports (5060-5061 for SIP, plus your RTP range) are open. Also, try disabling SIP helper with set sip-helper disable to avoid any other interference. After making those changes, reboot the firewall. Lastly, take another look at your 3CX settings—tweaking UDP vs TCP or codecs might solve the problem.