[OpenSIPS-Users] Failed INVITE tcp_send to UDP UACs

[opensipslist at encambio.com]

Hello list,

PROBLEM
-------

Registrations work well, but when sending IVITEs I see this in log:

  Dec 10 15:55:18 name.host.tld <debug> opensips[10848]: DBG:core:mk_proxy: doing DNS lookup...
  Dec 10 15:55:18 name.host.tld <debug> opensips[10848]: DBG:core:sip_resolvehost: no port, no proto -> do NAPTR lookup!
  Dec 10 15:55:18 name.host.tld <debug> opensips[10848]: DBG:core:filter_and_sort_naptr: skipping SIP+D2U -> _sip._udp.voip.host.tld
  Dec 10 15:55:18 name.host.tld <debug> opensips[10848]: DBG:core:filter_and_sort_naptr: found valid SIPS+D2T -> _sips._tcp.voip.host.tld
  Dec 10 15:55:18 name.host.tld <debug> opensips[10848]: DBG:core:filter_and_sort_naptr: skipping SIP+D2T -> _sip._tcp.voip.host.tld
  Dec 10 15:55:18 name.host.tld <debug> opensips[10848]: DBG:core:do_srv_lookup: SRV(_sips._tcp.voip.host.tld) = voip.host.tld:5061
  Dec 10 15:55:18 name.host.tld <debug> opensips[10848]: DBG:core:sip_resolvehost: valid SRV found!
  [...]
  Dec 10 15:55:18 name.host.tld <debug> opensips[10850]: DBG:core:send2child: to tcp child 0 0(10848), ceba0508
  Dec 10 15:55:18 name.host.tld <debug> opensips[10850]: DBG:core:handle_ser_child: read response= ceb903f0, 2, fd 21 from 6 (10848)
  Dec 10 15:55:18 name.host.tld <debug> opensips[10850]: DBG:core:tcpconn_add: hashes: 405, 3
  Dec 10 15:55:18 name.host.tld <debug> opensips[10850]: DBG:core:io_watch_add: io_watch_add(82d10c0, 21, 2, ceb903f0), fd_no=10
  Dec 10 15:55:18 name.host.tld <error> opensips[10848]: ERROR:core:tls_blocking_write: too many retries with no operation
  Dec 10 15:55:18 name.host.tld <debug> opensips[10848]: DBG:core:tcp_send: after write: c= ceb903f0 n=-1 fd=18
  Dec 10 15:55:18 name.host.tld <debug> opensips[10848]: DBG:core:tcp_send: buf=
  INVITE sips:person at voip.host.tld SIP/2.0^M
  Record-Route: <sip:211.123.22.12:5061;transport=tls;lr=on;ftag=grophp7yc3>^M
  Via: SIP/2.0/TLS 211.123.22.12:5061;branch=z9hG4bK4d6.913.0;i=2^M
  Via: SIP/2.0/TLS 192.168.1.12:3352;received=125.81.6.152;branch=z9hG4bK-pt7eil3u8qci;rport=3352^M
  [...]
  Content-Type: application/sdp^M
  ^@Dec 10 15:55:18 name.host.tld <error> opensips[10848]: ERROR:core:tcp_send: failed to send
  Dec 10 15:55:18 name.host.tld <error> opensips[10848]: ERROR:tm:msg_send: tcp_send failed
  Dec 10 15:55:18 name.host.tld <debug> opensips[10850]: DBG:core:handle_ser_child: read response= ceb903f0, -2, fd -1 from 6 (10848)
  Dec 10 15:55:18 name.host.tld <error> opensips[10848]: ERROR:tm:t_forward_nonack: sending request failed
  Dec 10 15:55:18 name.host.tld <debug> opensips[10850]: DBG:core:io_watch_del: io_watch_del (82d10c0, 21, -1, 0x10) fd_no=11 called
  Dec 10 15:55:18 name.host.tld <debug> opensips[10848]: DBG:tm:t_relay_to: t_forward_nonack returned error

The forward (I assume by t_relay()) is failing. Is it because a SRV
lookup is being done and finding that raw SIP over TCP is being sent
to the OpenSIPS TLS listener? Should I be using something other than
t_relay() in the config?

The same config worked well with OpenSER 1.3.X. Only when migrating
to 1.6.0 do we see these errors. What could have changed?

Thanks,
Brian