I have a FritzBox with a secondary openwrt router, where the freepbx (raspberry pi) is in the subnet of the router. The phones directly in the router subnet work fine.
Now I try to set up a trunk. In the FritzBox I created a pjsip LAN/WLAN device, that connects to a trunk in the freepbx node. I already opened all ports and created port forwardings in the router.
Still, when I get incoming calls on the FritzBox, nothing happens. In the Asterisk log, there are no entries at that time. In the tcpdump of the router, there are messages like
21:09:37.836896 IP 192.168.1.246 > 192.168.178.1: ICMP 192.168.1.246 udp port 5063 unreachable, length 556
where 192.168.178.1 is the IP of the FritzBox, 192.168.1.246 is the IP of the freepbx node.
Is someone willing to assist me? I know similar problems have been discussed already, but did not give me hints.