[SR-Users] Problem with Kamailio 4.2.0

Hi, I'm using Kamailio 4.2.0 and I'm developing a SIP-based application. Today I made a test connecting two devices directly to an S7 sharing the Internet, I usually use a VPN even if they are both connected to the same network because in the future they will be in different networks.Without the VPN calls were not received. This has never happened to me, I have repeated tests and in an S6 it has also happened to me. So I have checked my Kamailio server and I have detected that when executing: kamctl ul show, the received field did not appear: With VPN: Contact:: sip:pruebaT@47.60.42.40:10924;transport=udp Q= Expires:: 1992 Callid:: iwNoYb~QR- Cseq:: 21 User-agent:: Unknown (belle-sip/1.6.1) Received:: sip:47.60.42.40:10924 State:: CS_NEW Flags:: 0 Cflag:: 64 Socket:: udp:10.0.0.4:5060 Methods:: 4294967295 Ruid:: uloc-5a9d9097-9fa-431c Instance:: <urn:uuid:8b50dde3-d07f-4752-9a24-7b8ddf219a99> Reg-Id:: 0 Last-Keepalive:: 1539614732 Last-Modified:: 1539614732 Without VPN: Contact:: sip:pruebaT@37.10.156.189:51163;transport=udp Q= Expires:: 1996 Callid:: webjvHycBs Cseq:: 21 User-agent:: Unknown (belle-sip/1.6.1) State:: CS_NEW Flags:: 0 Cflag:: 0 Socket:: udp:10.0.0.4:5060 Methods:: 4294967295 Ruid:: uloc-5a9d9097-9fc-1feb Instance:: <urn:uuid:89306a81-e2d1-4b7a-8206-107e3cbc0688> Reg-Id:: 0 Last-Keepalive:: 1539614531 Last-Modified:: 1539614531 Would someone know why it happened? Thanks -- José Antonio Gutiérrez Delgado Responsable técnico Oficina: (+34) 923040031 <http://www.arsoft-company.com/> *Este mensaje se dirige exclusivamente a su destinatario/s y puede contener información privilegiada o confidencial. Si no es vd. el destinatario indicado, queda notificado de que la utilización, divulgación y/o copia sin autorización está prohibida en virtud de la legislación vigente. Si ha recibido este mensaje por error, le rogamos que nos lo comunique inmediatamente por esta misma vía y proceda a su destrucción.* *Antes de imprimir, piensa si es necesario. Cuidar el medioambiente es tarea de todos.*