Re: [SR-Users] TCP reset behavior

The scenario here is the other end's RESET/connection closure will never reach Kamailio, as the client has lost it's network connectivity. In such case expected Kamailio to reset the TCP connection after 120seconds based on the TCP keepalive config params mentioned earlier. From wireshark capture observe, Kamailio keeps resending TCP keepalive packets at varying intervals for varying duration length(like 6mins, 14mins..) before resetting the TCP connections. thanks, raj From: Daniel-Constantin Mierla &lt;miconda(a)gmail.com&gt; Sent: Wednesday, June 12, 2019 1:36 PM To: R, Rajkumar (Raj) &lt;rajkumaradass(a)avaya.com&gt;om>; Kamailio (SER) - Users Mailing List &lt;sr-users(a)lists.kamailio.org&gt; Subject: Re: [SR-Users] TCP reset behavior If it is established, then the other side didn't actually requested the close of the connection. It should be in close-wait state when the remote peer sent the close request. Look at the traffic of the connection with wireshare, it shows also the tcp control packets. On 12.06.19 09:57, R, Rajkumar (Raj) wrote: It remained in 'ESTABLISHED' state only. Please find netstat output below. # netstat -natlp Active Internet connections (servers and established) Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 0 0.0.0.0:5060 0.0.0.0:* LISTEN 20/kamailio tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN - tcp 0 0 0.0.0.0:411 0.0.0.0:* LISTEN - tcp 0 0 0.0.0.0:8443 0.0.0.0:* LISTEN - tcp 0 0 0.0.0.0:5056 0.0.0.0:* LISTEN 20/kamailio tcp 0 3777 10.1.4.55:5060 10.27.117.55:38115 ESTABLISHED 20/Kamailio thanks, raj +918067153382 From: Daniel-Constantin Mierla <miconda@gmail.com><mailto:miconda@gmail.com> Sent: Wednesday, June 12, 2019 12:29 PM To: R, Rajkumar (Raj) <rajkumaradass@avaya.com><mailto:rajkumaradass@avaya.com>; Kamailio (SER) - Users Mailing List <sr-users@lists.kamailio.org><mailto:sr-users@lists.kamailio.org> Subject: Re: [SR-Users] TCP reset behavior Hello, the connection state is OK in all outputs, so not seen as closed by Kamailio. Can you get the output of the netstat for that connection after is supposed to be closed to see its state there? Cheers, Daniel On 11.06.19 12:17, Daniel-Constantin Mierla wrote: Hello, I didn't get the time to look at. It was a long weekend in Germany, with Monday being public holiday. Not sure if I get to it today, but hope to get time in the next few days. Cheers, Daniel On 11.06.19 07:56, R, Rajkumar (Raj) wrote: Did the shared tcp stats help? Awaiting your inputs on this. thanks, raj From: sr-users <sr-users-bounces@lists.kamailio.org><mailto:sr-users-bounces@lists.kamailio.org> On Behalf Of R, Rajkumar (Raj) Sent: Friday, June 7, 2019 10:44 PM To: miconda@gmail.com<mailto:miconda@gmail.com>; Kamailio (SER) - Users Mailing List <sr-users@lists.kamailio.org><mailto:sr-users@lists.kamailio.org> Subject: Re: [SR-Users] TCP reset behavior Hi Daniel, Please find attached stats output captured every 2 seconds for the entire duration of test (i.e., Start of registration from client till the connection towards client is reset by kamailio after 17mins approximately). I had used 'kamcmd' instead of 'kamctl' for same command arguments. Setup: 10.27.117.55 (Client) --- Kamailio (10.1.4.55) ---- Backend server (10.2.8.70) Summary of events executed/observed during the test: * Once the client is registered successfully to the backend, turned off WiFi connection at the client side (time 13:07.05 UTC 2019). * After OPTIONS msg time out for response from the client, backend closes the TCP connection towards kamailio ( around time 13:10:39), * TCP connection towards client side is reset at 13:24:30 (i.e., 17 minutes since the WiFi is turned off) * In wireshark, see re-transmission of a TCP packet from kamailio for about 15 minutes until connection release. thanks, raj From: Daniel-Constantin Mierla <miconda@gmail.com<mailto:miconda@gmail.com>> Sent: Friday, June 7, 2019 6:14 PM To: Kamailio (SER) - Users Mailing List <sr-users@lists.kamailio.org<mailto:sr-users@lists.kamailio.org>>; R, Rajkumar (Raj) <rajkumaradass@avaya.com<mailto:rajkumaradass@avaya.com>> Subject: Re: [SR-Users] TCP reset behavior Hello, can you reproduce the case and then get the output of the next commands: kamctl rpc core.tcp_list kamctl rpc core.tcp_options kamctl rpc core.tcp_info Cheers, Daniel On 06.06.19 18:53, R, Rajkumar (Raj) wrote: Hi All, In our setup running kamailio (alpine image) in stateless mode and have following TCP config set. After client registers to the backend see two TCP connections created - one towards the client and the other towards the backendserver. If there's a abrupt network disconnect either at the client side or at the backend side, do not see TCP reset happening from kamailio as per the config. Per below config expected after 120seconds( = [tcp_keepidle] + ( [tcp_keepintvl * tcp_keepcnt] ) instead it keeps resending TCP keepalive packets at varying intervals for varying duration length(like 6mins, 14mins..) before resetting the TCP connections. Also want to mention that we are not using TCPOPS module here. I am trying to achieve consistent duration for TCP reset in kamailio. Could you please point me if I have missed anything here? Setup: Client ---- Kamailio (stateless mode) ---- Backend server TCP Config: tcp_connection_lifetime = 3600 tcp_accept_aliases = no tcp_async = yes tcp_connect_timeout = 10 tcp_crlf_ping = yes tcp_keepalive = yes tcp_keepcnt = 3 tcp_keepidle = 30 tcp_keepintvl = 30 # Total 2 mins - 30+(30*3)=120 sec tcp_linger2 = 30 tcp_rd_buf_size = 65536 tcp_send_timeout = 10 thanks, raj _______________________________________________ Kamailio (SER) - Users Mailing List sr-users@lists.kamailio.org<mailto:sr-users@lists.kamailio.org> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users<https://url… -- Daniel-Constantin Mierla -- www.asipto.com<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.a… www.twitter.com/miconda<https://urldefense.proofpoint.com/v2/url?u=http-… -- www.linkedin.com/in/miconda<https://urldefense.proofpoint.com/v2/url?u=h… -- Daniel-Constantin Mierla -- www.asipto.com<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.a… www.twitter.com/miconda<https://urldefense.proofpoint.com/v2/url?u=http-… -- www.linkedin.com/in/miconda<https://urldefense.proofpoint.com/v2/url?u=h… -- Daniel-Constantin Mierla -- www.asipto.com<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.a… www.twitter.com/miconda<https://urldefense.proofpoint.com/v2/url?u=http-… -- www.linkedin.com/in/miconda<https://urldefense.proofpoint.com/v2/url?u=h… -- Daniel-Constantin Mierla -- www.asipto.com<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.a… www.twitter.com/miconda<https://urldefense.proofpoint.com/v2/url?u=http-… -- www.linkedin.com/in/miconda<https://urldefense.proofpoint.com/v2/url?u=h…