- This gives an option to also send RST in case kamailio closes the connection. There are cases where a FIN,ACK back forth leaves the connection in the host in TIME_WAIT state, but the ports on both sides are fixed. This leads to no request can send until the TIME_WAIT state is gone.

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#### Description <!-- Describe your changes in detail --> We have seen that in deployments where there are strict port requirements on both side, there are tcp connections in TIME_WAIT state causing no fresh TCP connections possible until the TIME_WAIT is gone. In a lot of these case the clients are sending from them self a RST after they send a FIN,ACK from there side but some aren't doing this. The basic idea of this PR is to give an extra option for the tcp configuration from the cfg to trigger always an RST on connection close from Kamailio side. This currently done by enabling SO_LINGER with a value of 0 just before close.

You can view, comment on, or merge this pull request online at:

https://github.com/kamailio/kamailio/pull/3100

-- Commit Summary --

* core: add an option to trigger also an RST on tcp connection close

-- File Changes --

M src/core/cfg.lex (2) M src/core/cfg.y (9) M src/core/tcp_main.c (7) M src/core/tcp_options.c (3) M src/core/tcp_options.h (1)

-- Patch Links --

https://github.com/kamailio/kamailio/pull/3100.patch https://github.com/kamailio/kamailio/pull/3100.diff