Solved Calls hanging up after 32 seconds

[Piotr_INS]

Hi,
all inbound calls hanging up after 32 seconds and all outbound calls not working. 3cx firewall checker is all green. Local firewall and configuration of FortiGate looks ok because everything worked good. Where to look for the cause of the problem? Is it on the provider's side?

 

[JohnS_3CX]

We can clearly see that the INVITE is coming in from a LAN IP so the PBX treats it as local traffic and this breaks the SIP communication (ending the call at 32 sec.)

I'm afraid it looks like your firewall is messing up the traffic (by re-writing the IP addresses), and there is nothing you can do on the 3CX system that can fix that..

 

[JohnS_3CX]

Also, modifying these will not help you not matter what you do.
Figure out why the firewall is re-writing the IP addresses and prevent it from doing so.

 

[Piotr_INS]

@JohnS_3CX thank you so much.

after changing to public IP here:

incoming calls are fine but not outgoing.

Is there any detailed instruction how to configure firewall and FortiGate 60E? I heard that there are some problems with FortiGate.

Anyway, thank you, now I know a little bit more ;D

 

[Piotr_INS]

It worked fine with current FortiGate configuration, I don't know, I'll be keep looking.

 

[JohnS_3CX]

We have a guide you might find helpful, not sure if it applies to your specific model but it may have a few key areas that will help.
https://www.3cx.com/docs/fortigate-firewall-configuration/

 

[Piotr_INS]

We have done this configuration before but thank you anyway.

 

[JohnS_3CX]

In that case I would suggest to get in touch with the Fortigate specialists and see if they can assist you.

You can describe to them that while the traffic comes from an external IP 80.x.x.x the internal clients see the traffic coming from an internal IP 192.x.x.x

I think it will likely be a matter of NAT configuration.

 

[Piotr_INS]

Ok, thank you so much

 

[Piotr_INS]

I will let you know what was the problem.

 

[JohnS_3CX]

Searching for fortinet on the forum might also get you some useful results from other members. For example:
https://www.3cx.com/community/threa...t-failed-port-9000-onwards.77589/#post-355471

I'm really not sure how you passed the firewall checker based on the capture we saw yesterday, I would expect that to fail. Will it pass if you run it again I wonder

 

[Piotr_INS]

Yeah, firewall checker all green.

 

[Piotr_INS]

Hello, @JohnS_3CX as you said it was NAT configuration. Aftter changing NAT setting in FortiGate Firewall Policy to Disabled everything works fine. Small but important detail. It is strange because it worked before without this setting.

 

[JohnS_3CX]

Hi @Piotr_INS

That's very good news!

I am not in a position to say why / how it worked before, then again we do not have any data from before to compare