Hello,

I'm observing a bit strange behavoir of Kamailio, but maybe I'm wrong in my assumptions.

In some cases Kamailio just closes absolutely valid TCP connection, as I see it in Wireshark

At the same time I do see in Kamailio logs a lots of lines with

tcp_timer_check_connections(): message processing timeout on connection id: XXXXX (state: 0) - closing

I see that many TCP connections are closing (and it's ok as we have mobile devices connected and loosing connections for them is ok)

But for me this connection is perfectly ok looking on TCP keepalives, what can cause this behavoir?

I have these TCP options

tcp_connect_timeout=30
tcp_conn_wq_max=63536
tcp_crlf_ping=yes
tcp_delayed_ack=yes
tcp_fd_cache=yes
tcp_keepalive=yes
tcp_keepcnt=3
tcp_keepidle=30
tcp_keepintvl=10
tcp_linger2=30

Kamailio 5.8.3

Any hints are appreciated.