replace my FQDN with
fqdn.wan.3cx.us
Replace my WAN ip on the server with
wan.ip.my.server
here is the debug
NOTICE | 20161123-005614.098 | 3CXTunnel | TUNL | 5932 | Log.cpp:35 | Log started: type = file, level = ERR,DEBUG
INFO | 20161123-005614.112 | 3CXTunnel | RESIP

NS | 5932 | DnsUtil.cxx:170 | local hostname does not contain a domain part Richard-PC
INFO | 20161123-005614.112 | 3CXTunnel | TUNL | 5932 | RPiTunnel.cpp:161 | Local host name: Richard-PC
NOTICE | 20161123-005614.112 | 3CXTunnel | TUNL | 5932 | Bridge.cpp:1061 | Check:
Bridge config: [Bridge/123456]
#Mandatory:
ID = 123456
Password = 137W141st_
TunnelFqdn = fqdn.wan.3cx.us
#Optional
SecurityMode = 1
ClientsCertificateFile ''
ClientsPrivateKeyFile ''
PBX SIP addr = fqdn.wan.3cx.us:5060
Name = 3CXSBC15.0.56341
LocalSipAddr = 10.0.0.6
LocalSipPort = 5060
NumRtpPorts = 8
#===========
DEBUG | 20161123-005614.113 | 3CXTunnel | RESIP | 5932 | Security.cxx:1075 | BaseSecurity::BaseSecurity
WARNING | 20161123-005614.292 | 3CXTunnel | RESIP | 5932 | Security.cxx:2966 | unable to load DH parameters (required for PFS): TlsDHParamsFilename not specified
DEBUG | 20161123-005614.293 | 3CXTunnel | RESIP | 5932 | Security.cxx:3023 | ECDH initialized
WARNING | 20161123-005614.294 | 3CXTunnel | RESIP | 5932 | Security.cxx:2966 | unable to load DH parameters (required for PFS): TlsDHParamsFilename not specified
DEBUG | 20161123-005614.294 | 3CXTunnel | RESIP | 5932 | Security.cxx:3023 | ECDH initialized
INFO | 20161123-005614.300 | 3CXTunnel | RESIP

NS | 5932 | AresDns.cxx:369 | DNS initialization: found 5 name servers
INFO | 20161123-005614.300 | 3CXTunnel | RESIP

NS | 5932 | AresDns.cxx:380 | name server: 8.8.8.8
INFO | 20161123-005614.300 | 3CXTunnel | RESIP

NS | 5932 | AresDns.cxx:380 | name server: 4.4.4.4
INFO | 20161123-005614.300 | 3CXTunnel | RESIP

NS | 5932 | AresDns.cxx:380 | name server: 192.168.13.1
INFO | 20161123-005614.300 | 3CXTunnel | RESIP

NS | 5932 | AresDns.cxx:380 | name server: 196.3.81.5
INFO | 20161123-005614.300 | 3CXTunnel | RESIP

NS | 5932 | AresDns.cxx:380 | name server: 200.88.127.22
DEBUG | 20161123-005614.300 | 3CXTunnel | RESIP | 5932 | Compression.cxx:44 | COMPRESSION SUPPORT NOT COMPILED IN
DEBUG | 20161123-005614.300 | 3CXTunnel | RESIP | 5932 | Compression.cxx:47 | Compression configuration object created; algorithm = 0
DEBUG | 20161123-005614.300 | 3CXTunnel | RESIP:TRANSPORT | 5932 | TransportSelector.cxx:99 | No compression library available
DEBUG | 20161123-005614.301 | 3CXTunnel | RESIP:TRANSPORT | 5932 | InternalTransport.cxx:121 | Creating fd=560 V4/UDP
DEBUG | 20161123-005614.301 | 3CXTunnel | RESIP:TRANSPORT | 5932 | InternalTransport.cxx:133 | Binding to 10.0.0.6
INFO | 20161123-005614.301 | 3CXTunnel | RESIP:TRANSPORT | 5932 | UdpTransport.cxx:54 | Creating UDP transport host=10.0.0.6 port=5060 ipv4=1
DEBUG | 20161123-005614.301 | 3CXTunnel | RESIP:TRANSPORT | 5932 | UdpTransport.cxx:68 | No compression library available: Transport: [ V4 10.0.0.6:5060 UDP flowKey=560 ] on 10.0.0.6
NOTICE | 20161123-005614.301 | 3CXTunnel | TUNL | 5932 | Bridge.cpp:47 | Main local UDP transport is bound to 10.0.0.6:5060
NOTICE | 20161123-005614.301 | 3CXTunnel | TUNL | 5932 | Bridge.cpp:63 | SIP UDP transport on 10.0.0.6:5060 is joined to multicast group 224.0.1.75
DEBUG | 20161123-005614.301 | 3CXTunnel | RESIP | 5932 | SipStack.cxx:678 | Adding domain alias: 10.0.0.6:5060
DEBUG | 20161123-005614.301 | 3CXTunnel | RESIP:TRANSPORT | 5932 | TransportSelector.cxx:221 | Adding transport: [ V4 10.0.0.6:5060 UDP transportKey=1 ]
INFO | 20161123-005614.301 | 3CXTunnel | RESIP:TRANSPORT | 5932 | TransportSelector.cxx:293 | TransportSelector::addTransport: added transport for tuple=[ V4 10.0.0.6:5060 UDP transportKey=1 ], key=1
DEBUG | 20161123-005614.301 | 3CXTunnel | RESIP:TRANSPORT | 5932 | InternalTransport.cxx:121 | Creating fd=564 V4/UDP
NOTICE | 20161123-005614.301 | 3CXTunnel | TUNL | 5932 | Rtp.cpp:104 | RTP socket 564 is bound to 0.0.0.0:58082
DEBUG | 20161123-005614.301 | 3CXTunnel | RESIP:TRANSPORT | 5932 | InternalTransport.cxx:121 | Creating fd=568 V4/UDP
NOTICE | 20161123-005614.301 | 3CXTunnel | TUNL | 5932 | Rtp.cpp:104 | RTP socket 568 is bound to 0.0.0.0:58084
DEBUG | 20161123-005614.301 | 3CXTunnel | RESIP:TRANSPORT | 5932 | InternalTransport.cxx:121 | Creating fd=572 V4/UDP
NOTICE | 20161123-005614.301 | 3CXTunnel | TUNL | 5932 | Rtp.cpp:104 | RTP socket 572 is bound to 0.0.0.0:58086
DEBUG | 20161123-005614.301 | 3CXTunnel | RESIP:TRANSPORT | 5932 | InternalTransport.cxx:121 | Creating fd=576 V4/UDP
NOTICE | 20161123-005614.301 | 3CXTunnel | TUNL | 5932 | Rtp.cpp:104 | RTP socket 576 is bound to 0.0.0.0:58088
DEBUG | 20161123-005614.301 | 3CXTunnel | RESIP:TRANSPORT | 5932 | InternalTransport.cxx:121 | Creating fd=580 V4/UDP
NOTICE | 20161123-005614.301 | 3CXTunnel | TUNL | 5932 | Rtp.cpp:104 | RTP socket 580 is bound to 0.0.0.0:58090
DEBUG | 20161123-005614.301 | 3CXTunnel | RESIP:TRANSPORT | 5932 | InternalTransport.cxx:121 | Creating fd=584 V4/UDP
NOTICE | 20161123-005614.301 | 3CXTunnel | TUNL | 5932 | Rtp.cpp:104 | RTP socket 584 is bound to 0.0.0.0:58092
DEBUG | 20161123-005614.301 | 3CXTunnel | RESIP:TRANSPORT | 5932 | InternalTransport.cxx:121 | Creating fd=588 V4/UDP
NOTICE | 20161123-005614.301 | 3CXTunnel | TUNL | 5932 | Rtp.cpp:104 | RTP socket 588 is bound to 0.0.0.0:58094
DEBUG | 20161123-005614.301 | 3CXTunnel | RESIP:TRANSPORT | 5932 | InternalTransport.cxx:121 | Creating fd=592 V4/UDP
NOTICE | 20161123-005614.301 | 3CXTunnel | TUNL | 5932 | Rtp.cpp:104 | RTP socket 592 is bound to 0.0.0.0:58096
DEBUG | 20161123-005614.302 | 3CXTunnel | RESIP:TRANSPORT | 5932 | InternalTransport.cxx:121 | Creating fd=624 V4/TCP
DEBUG | 20161123-005614.302 | 3CXTunnel | RESIP:TRANSPORT | 5932 | InternalTransport.cxx:133 | Binding to 0.0.0.0
NOTICE | 20161123-005614.306 | 3CXTunnel | TUNL | 5932 | TunnelTcp.cpp:103 | TCP socket (624) is created and bound to [ V4 0.0.0.0:63862 UNKNOWN_TRANSPORT ]
MAC=FC:AA:14:97:B9:9F; MAC hash = 2776813919
DEBUG | 20161123-005614.306 | 3CXTunnel | RESIP:TRANSPORT | 5932 | InternalTransport.cxx:121 | Creating fd=628 V4/UDP
NOTICE | 20161123-005614.306 | 3CXTunnel | TUNL | 5932 | TunnelTcp.cpp:154 | UDP listener is bound to 0.0.0.0:63862
NOTICE | 20161123-005614.306 | 3CXTunnel | TUNL | 5932 | Bridge.cpp:131 | Tunnel host unique ID=sbc.a582d15f
NOTICE | 20161123-005614.306 | 3CXTunnel | TUNL | 5932 | TunnelTcp.cpp:173 | Trying to resolve tunnel connection to destination's FQDN fqdn.wan.3cx.us
INFO | 20161123-005614.309 | 3CXTunnel | RESIP

NS | 5932 | AresDns.cxx:369 | DNS initialization: found 5 name servers
INFO | 20161123-005614.309 | 3CXTunnel | RESIP

NS | 5932 | AresDns.cxx:380 | name server: 8.8.8.8
INFO | 20161123-005614.309 | 3CXTunnel | RESIP

NS | 5932 | AresDns.cxx:380 | name server: 4.4.4.4
INFO | 20161123-005614.309 | 3CXTunnel | RESIP

NS | 5932 | AresDns.cxx:380 | name server: 192.168.13.1
INFO | 20161123-005614.309 | 3CXTunnel | RESIP

NS | 5932 | AresDns.cxx:380 | name server: 196.3.81.5
INFO | 20161123-005614.309 | 3CXTunnel | RESIP

NS | 5932 | AresDns.cxx:380 | name server: 200.88.127.22
INFO | 20161123-005614.309 | 3CXTunnel | TUNL | 5932 | Dns.cpp:7 | [DNS] Resolving SRV records for _3cxtunnel._tcp.fqdn.wan.3cx.us
DEBUG | 20161123-005614.379 | 3CXTunnel | RESIP

NS | 5932 | DnsStub.cxx:67 | _3cxtunnel._tcp.fqdn.wan.3cx.us (SRV) --> p=10 w=0 fqdn.wan.3cx.us:5090
DEBUG | 20161123-005614.379 | 3CXTunnel | TUNL | 5932 | Dns.cpp:138 | [DNS] Got DNS SRV result for _3cxtunnel._tcp.fqdn.wan.3cx.us: status = 0
INFO | 20161123-005614.379 | 3CXTunnel | TUNL | 5932 | Dns.cpp:58 | [DNS} Got SRV record: target fqdn.wan.3cx.us:5090; priority=10, weight=0
INFO | 20161123-005614.379 | 3CXTunnel | TUNL | 5932 | Dns.cpp:89 | [DNS] Resolving IP address(es) for fqdn.wan.3cx.us
DEBUG | 20161123-005614.443 | 3CXTunnel | RESIP

NS | 5932 | DnsStub.cxx:49 | fqdn.wan.3cx.us(A)--> wan.ip.my.server
DEBUG | 20161123-005614.443 | 3CXTunnel | TUNL | 5932 | Dns.cpp:149 | [DNS] Got DNS A result for fqdn.wan.3cx.us: status = 0
INFO | 20161123-005614.443 | 3CXTunnel | TUNL | 5932 | Dns.cpp:123 | [DNS] Resolved host name fqdn.wan.3cx.us to [wan.ip.my.server]
NOTICE | 20161123-005614.443 | 3CXTunnel | TUNL | 5932 | TunnelTcp.cpp:268 | Making TCP connection to [ V4 wan.ip.my.server:5090 TCP ]
DEBUG | 20161123-005614.518 | 3CXTunnel | TUNL | 6000 | security.cpp:1072 | Ready to send, send q size = 0
NOTICE | 20161123-005614.518 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:532 | Tunnel connection to [ V4 wan.ip.my.server:5090 TCP ] is accepted
ALERT | 20161123-005614.518 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:583 | Sending first packet from [ V4 0.0.0.0:63862 UNKNOWN_TRANSPORT ] to [ V4 wan.ip.my.server:5090 TCP ]
DEBUG | 20161123-005614.526 | 3CXTunnel | TUNL | 6000 | security.cpp:626 | Creating SSL BIO on socket 624
NOTICE | 20161123-005614.526 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:680 | Sending keep-alive. Stats: KA sent: 1, KA recv: 0
NOTICE | 20161123-005614.527 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:498 | === Statistics:
Keep-alives: recv 0, sent 1
Transfers: recv last 75 ms ago, total 0 bytes
sent last 18446744073709551608 ms ago, total 63 bytes
===
INFO | 20161123-005614.594 | 3CXTunnel | TUNL | 6000 | security.cpp:1299 | Keep-alive received
DEBUG | 20161123-005614.971 | 3CXTunnel | TUNL | 6000 | security.cpp:1264 | Packet of 4 bytes is received and put in recvQ, qsize=1
WARNING | 20161123-005614.971 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:554 | Tunnel connection to [ V4 wan.ip.my.server:5090 TCP ] is disconnected; error: Connection is terminated by peer - while begin to read a packet from tunnel
ERR | 20161123-005614.971 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:295 | Bridge [3CXSBC15.0.56341] failure 'Connection is terminated by peer - while begin to read a packet from tunnel' on TCP connection: TunnelTcp:

rocess
NOTICE | 20161123-005614.971 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:498 | === Statistics:
Keep-alives: recv 1, sent 1
Transfers: recv last 0 ms ago, total 16 bytes
sent last 445 ms ago, total 63 bytes
===
WARNING | 20161123-005614.971 | 3CXTunnel | TUNL | 6000 | Bridge.cpp:243 | Tunnel disconnected. Terminating all active calls.
NOTICE | 20161123-005614.971 | 3CXTunnel | TUNL | 6000 | Bridge.cpp:353 | Unknown packet: signature = DROP
DEBUG | 20161123-005614.971 | 3CXTunnel | TUNL | 6000 | Bridge.cpp:354 | Dump:
--------
0000: 44 52 4F 50 DROP
DEBUG | 20161123-005614.971 | 3CXTunnel | RESIP:TRANSPORT | 6000 | InternalTransport.cxx:121 | Creating fd=628 V4/TCP
DEBUG | 20161123-005614.971 | 3CXTunnel | RESIP:TRANSPORT | 6000 | InternalTransport.cxx:133 | Binding to 0.0.0.0
NOTICE | 20161123-005614.974 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:103 | TCP socket (628) is created and bound to [ V4 0.0.0.0:63863 UNKNOWN_TRANSPORT ]
MAC=FC:AA:14:97:B9:9F; MAC hash = 2776813919
DEBUG | 20161123-005614.974 | 3CXTunnel | RESIP:TRANSPORT | 6000 | InternalTransport.cxx:121 | Creating fd=692 V4/UDP
NOTICE | 20161123-005614.974 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:154 | UDP listener is bound to 0.0.0.0:63863
NOTICE | 20161123-005614.974 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:173 | Trying to resolve tunnel connection to destination's FQDN fqdn.wan.3cx.us
INFO | 20161123-005614.974 | 3CXTunnel | TUNL | 6000 | Dns.cpp:7 | [DNS] Resolving SRV records for _3cxtunnel._tcp.fqdn.wan.3cx.us
DEBUG | 20161123-005614.975 | 3CXTunnel | RESIP

NS | 6000 | DnsStub.cxx:67 | _3cxtunnel._tcp.fqdn.wan.3cx.us (SRV) --> p=10 w=0 fqdn.wan.3cx.us:5090
DEBUG | 20161123-005614.975 | 3CXTunnel | TUNL | 6000 | Dns.cpp:138 | [DNS] Got DNS SRV result for _3cxtunnel._tcp.fqdn.wan.3cx.us: status = 0
INFO | 20161123-005614.975 | 3CXTunnel | TUNL | 6000 | Dns.cpp:58 | [DNS} Got SRV record: target fqdn.wan.3cx.us:5090; priority=10, weight=0
INFO | 20161123-005614.975 | 3CXTunnel | TUNL | 6000 | Dns.cpp:89 | [DNS] Resolving IP address(es) for fqdn.wan.3cx.us
DEBUG | 20161123-005614.975 | 3CXTunnel | RESIP

NS | 6000 | DnsStub.cxx:49 | fqdn.wan.3cx.us(A)--> wan.ip.my.server
DEBUG | 20161123-005614.975 | 3CXTunnel | TUNL | 6000 | Dns.cpp:149 | [DNS] Got DNS A result for fqdn.wan.3cx.us: status = 0
INFO | 20161123-005614.975 | 3CXTunnel | TUNL | 6000 | Dns.cpp:123 | [DNS] Resolved host name fqdn.wan.3cx.us to [wan.ip.my.server]
NOTICE | 20161123-005614.975 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:268 | Making TCP connection to [ V4 wan.ip.my.server:5090 TCP ]
DEBUG | 20161123-005615.051 | 3CXTunnel | TUNL | 6000 | security.cpp:1072 | Ready to send, send q size = 0
NOTICE | 20161123-005615.051 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:532 | Tunnel connection to [ V4 wan.ip.my.server:5090 TCP ] is accepted
ALERT | 20161123-005615.051 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:583 | Sending first packet from [ V4 0.0.0.0:63863 UNKNOWN_TRANSPORT ] to [ V4 wan.ip.my.server:5090 TCP ]
DEBUG | 20161123-005615.059 | 3CXTunnel | TUNL | 6000 | security.cpp:626 | Creating SSL BIO on socket 628
NOTICE | 20161123-005615.059 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:680 | Sending keep-alive. Stats: KA sent: 1, KA recv: 0
INFO | 20161123-005616.088 | 3CXTunnel | TUNL | 6000 | security.cpp:1299 | Keep-alive received
DEBUG | 20161123-005616.088 | 3CXTunnel | TUNL | 6000 | security.cpp:1264 | Packet of 4 bytes is received and put in recvQ, qsize=1
NOTICE | 20161123-005616.088 | 3CXTunnel | TUNL | 6000 | Bridge.cpp:353 | Unknown packet: signature = DROP
DEBUG | 20161123-005616.088 | 3CXTunnel | TUNL | 6000 | Bridge.cpp:354 | Dump:
--------
0000: 44 52 4F 50 DROP
WARNING | 20161123-005616.092 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:554 | Tunnel connection to [ V4 wan.ip.my.server:5090 TCP ] is disconnected; error: Connection is terminated by peer - while begin to read a packet from tunnel
ERR | 20161123-005616.092 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:295 | Bridge [3CXSBC15.0.56341] failure 'Connection is terminated by peer - while begin to read a packet from tunnel' on TCP connection: TunnelTcp:

rocess
NOTICE | 20161123-005616.092 | 3CXTunnel | TUNL | 6000 | TunnelTcp.cpp:498 | === Statistics:
Keep-alives: recv 1, sent 1
Transfers: recv last 4 ms ago, total 16 bytes
sent last 1033 ms ago, total 63 bytes
===
WARNING | 20161123-005616.092 | 3CXTunnel | TUNL | 6000 | Bridge.cpp:243 | Tunnel disconnected. Terminating all active calls.