### Description Kamailio server has two legs that are connected to different networks. I'm using Kamailio v.5.2.3 and the "enable_double_rr" is implicitly set to "1". The leg "A" IP address is 10.28.80.1 The leg "B" IP address is 192.168.9.103 The call is initiated from 10.28.80.47
According to the "rr" module documentation, function record_route() should insert two "Record_Route" header fields when a request is accepted on one leg is should go out via the second leg. This works as expected in case of UDP protocol:
INVITE sip:2601@192.168.0.178:49162;transport=udp SIP/2.0 Record-Route: sip:192.168.9.103;r2=on;lr;did=e2c.a191 Record-Route: sip:10.28.80.1;r2=on;lr;did=e2c.a191 Via: SIP/2.0/UDP 192.168.9.103;branch=z9hG4bKcfa5.d64ecbd87d5315b5993c4ccf16f86537.0 Via: SIP/2.0/UDP 10.28.80.47:5060;rport=5060;branch=z9hG4bK3a9e9a4d
But when the TCP protocol is used AND "listen" parameters are defined: listen=udp:10.28.80.1:5060 listen=tcp:10.28.80.1:5060 listen=udp:192.168.9.103:5060 listen=tcp:192.168.9.103:5060
then the outbound message looks like this:
INVITE sip:2601@192.168.0.178:48758;transport=tcp SIP/2.0 Record-Route: sip:10.28.80.1;transport=tcp;lr;did=bcd.72f Via: SIP/2.0/TCP 10.28.80.1;branch=z9hG4bKb9ca.26ea08654c9dbc32bb0dc6e3b6f92d45.0;i=3 Via: SIP/2.0/TCP 10.28.80.47:5060;rport=33976;branch=z9hG4bK5291fab1
There are two problems there: a) only one Record-Route with leg "A" is inserted b) the added "Via" header field contains the leg "A" IP address instead of expected leg "B" IP address (192.168.9.103). In the LAN trace, I see that in reality the message was sent from leg "B".
IMPORTANT: The problem occurs only when the "listen" parameters are defined in the Kamailio configuration. When the "listens" are not configured then everything works correctly.
### Troubleshooting
#### Reproduction
#### Debugging Data #### Log Messages http://updates.xorcom.com/~xorcom/kam-tcp-problem.tar.gz The archive contains the following files: * syslog-bad.log and bad.cap - Kamailio log and tcpdump trace of a call when the problem occurs * syslog-good.log and good.cap - Kamailio log and tcpdump trace of a call when the problem doesn't occur
#### SIP Traffic
### Possible Solutions ### Additional Information
kamailio -v version: kamailio 5.2.3 (x86_64/linux) flags: STATS: Off, USE_TCP, USE_TLS, USE_SCTP, TLS_HOOKS, USE_RAW_SOCKS, DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MEM, SHM_MMAP, PKG_MALLOC, Q_MALLOC, F_MALLOC, TLSF_MALLOC, DBG_SR_MEMORY, USE_FUTEX, FAST_LOCK-ADAPTIVE_WAIT, USE_DNS_CACHE, USE_DNS_FAILOVER, USE_NAPTR, USE_DST_BLACKLIST, HAVE_RESOLV_RES ADAPTIVE_WAIT_LOOPS=1024, MAX_RECV_BUFFER_SIZE 262144 MAX_URI_SIZE 1024, BUF_SIZE 65535, DEFAULT PKG_SIZE 8MB poll method support: poll, epoll_lt, epoll_et, sigio_rt, select. id: unknown compiled with gcc 7.3.0
***Operating System**:
Ubuntu 18.0.4