Hi all,

I’ve configured Kamailio to use TLS and it has two NICs, 192.x.x.x extern to a PSTN and 10.250.5.74 intern to FreeSWITCH. Kamailio has „listen=tls:10.250.5.74:5071“ and later on in the config I fire „force_send_socket(tls:10.250.5.74:5071)“. For some reason on calls from FreeSWITCH via Kamailkio to PSTN the TLS works but the other way around if Kamailio should do TLS to FreeSWITCH it throws this warning:
„/kamailio[3308]: WARNING: <core> [forward.c:231]: get_send_socket2(): protocol/port mismatch (forced tls:10.250.5.74:5071, to udp:10.250.5.72:5071)“
As a result of this Kamailio tries to send the PSTN INVITE via UDP and also tries to use the external IP (192.x.x.x) and of course this can’t work.

Why is it throwing this warning and how to understand it?

Best regards

Dimitry Nagorny

Trainee