[SR-Users] kamailio as UAC and NAPTR / sendsocket question

[Daniel Tryba]

On Wed, Jul 03, 2019 at 06:38:28PM +0200, Karsten Horsmann wrote:
> any one here that can imagine why force sendsocket generates an udp packet
> if the target accept only tcp? And without fs it generates an tcp packet.
> For uac registrations outbound?

Reading the cookbook documentation of force_send_socket raises
questions:
 Force to send the message from the specified socket (it _must_ be one
 of the sockets specified with the listen directive). If the
 protocol doesn't match (e.g. UDP message forced to a TCP
 socket) the closest socket of the same protocol is used. 

It relates to the listen directive, but if you are listening on a TCP
port/socket you can't use that port/socket to create new outbound
connections (to the best of my knowledge).

You already tried $fs but without proto and port:
https://www.kamailio.org/wiki/cookbooks/5.2.x/pseudovariables#fs_-_forced_socket
proto is taken from $du if missing and I guess port is 5060 if missing.
So if you are listening on 5060 tcp that can't be used for the outbound
message, 5060 from udp is the closed match perhaps.