root@comcerto:/# tcpdump -i any port 5060 -v
tcpdump: listening on any, link-type LINUX_SLL (Linux cooked v1), capture size 262144 bytes
09:09:34.433188 IP (tos 0x68, ttl 64, id 0, offset 0, flags [DF], proto UDP (17), length 1017)
    localhost..6060 > localhost..5060: SIP, length: 989
        INVITE sip:22@192.168.20.120 SIP/2.0
        Via: SIP/2.0/UDP 127.0.0.1:6060;rport;branch=z9hG4bK1421054365
        From: <sip:11@192.168.20.120>;tag=1556864564
        To: <sip:22@192.168.20.120>
        Call-ID: 1399772870
        CSeq: 20 INVITE
        Contact: <sip:11@127.0.0.1:6060>
        Content-Type: application/sdp
        Allow: INVITE,ACK,BYE,CANCEL,OPTIONS,REFER,NOTIFY,INFO,UPDATE,PRACK,SUBSCRIBE
        Max-Forwards: 70
        User-Agent: eXosip/5.3.0
        X-Endpoint-Type: FS01
        Allow-Events: conference
        Supported: replaces,timer,100rel
        Content-Length:   478

        v=0
        o=gateway 0 4 IN IP4 192.168.20.120
        s=conversation
        c=IN IP4 192.168.20.120
        t=0 0
        m=audio 10508 RTP/AVP 8 0 4 9 18 100 96 99 97 101 13 98
        a=rtpmap:8 PCMA/8000
        a=rtpmap:0 PCMU/8000
        a=rtpmap:4 G723/8000
        a=rtpmap:9 G722/8000
        a=rtpmap:18 G729/8000
        a=rtpmap:100 G726-40/8000
        a=rtpmap:96 G726-32/8000
        a=rtpmap:99 G726-24/8000
        a=rtpmap:97 G726-16/8000
        a=rtpmap:101 telephone-event/8000
        a=fmtp:101 0-15
        a=rtpmap:13 CN/8000
        a=rtpmap:98 PCMA/8000
        a=gpmd:98 vbd=yes
09:09:34.456359 IP (tos 0x0, ttl 64, id 55168, offset 0, flags [DF], proto TCP (6), length 52)
    192.168.20.120.46206 > 192.168.0.124.5060: Flags [S], cksum 0x0838 (correct), seq 976402260, win 5840, options [mss 1460,nop,nop,sackOK,nop,wscale 2], length 0
09:09:34.540845 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto UDP (17), length 251)
    localhost..5060 > localhost..6060: SIP, length: 223
        SIP/2.0 100 Trying
        Via: SIP/2.0/UDP 127.0.0.1:6060;rport=6060;branch=z9hG4bK1421054365
        To: <sip:22@192.168.20.120>
        From: <sip:11@192.168.20.120>;tag=1556864564
        Call-ID: 1399772870
        CSeq: 20 INVITE
        Content-Length: 0

09:09:37.450347 IP (tos 0x0, ttl 64, id 55169, offset 0, flags [DF], proto TCP (6), length 52)
    192.168.20.120.46206 > 192.168.0.124.5060: Flags [S], cksum 0x0838 (correct), seq 976402260, win 5840, options [mss 1460,nop,nop,sackOK,nop,wscale 2], length 0
09:09:37.572157 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto UDP (17), length 363)
    localhost..5060 > localhost..6060: SIP, length: 335
        SIP/2.0 500 Transport failure: no transports left to try
        Via: SIP/2.0/UDP 127.0.0.1:6060;rport=6060;branch=z9hG4bK1421054365
        To: <sip:22@192.168.20.120>;tag=2b46dd31
        From: <sip:11@192.168.20.120>;tag=1556864564
        Call-ID: 1399772870
        CSeq: 20 INVITE
        Warning: 399 comcerto "No other DNS entries to try (7,113)"
        Content-Length: 0

09:09:37.576640 IP (tos 0x68, ttl 64, id 0, offset 0, flags [DF], proto UDP (17), length 271)
    localhost..6060 > localhost..5060: SIP, length: 243
        ACK sip:22@192.168.20.120 SIP/2.0
        Via: SIP/2.0/UDP 127.0.0.1:6060;rport;branch=z9hG4bK1421054365
        From: <sip:11@192.168.20.120>;tag=1556864564
        To: <sip:22@192.168.20.120>;tag=2b46dd31
        Call-ID: 1399772870
        CSeq: 20 ACK
        Content-Length: 0


6 packets captured
10 packets received by filter
0 packets dropped by kernel
root@comcerto:/#