<div dir="ltr">Yes, the SUBSCRIBE was sent continuously 2~3 times captured by wireshark,<div>I tested using Ekiga as the sip client on windows 7.</div><div><br></div><div>However, after I rebooted the pc and re-test  this,</div><div>it only send one SUBSCRIBE now no matter how I tried,</div><div>even I changed the codes back.</div><div><br></div><div>And as you said, "<span style="font-size:14px">it means that the same SUBSCRIBE was already processed...</span>",<br></div><div>but I think it should send 200 OK and the NOTIFY back in a normal situation if it is indeed processed,</div><div>rather than stopping there when it received a retransmitted SIP message.</div><div><br></div><div>I can not generate the situation now, but I'll keep watching for this. </div><div><br></div><div>Thanks. :)</div></div><div class="gmail_extra"><br><div class="gmail_quote">2017-10-11 15:52 GMT+08:00 Daniel-Constantin Mierla <span dir="ltr"><<a href="mailto:miconda@gmail.com" target="_blank">miconda@gmail.com</a>></span>:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
  
    
  
  <div text="#000000" bgcolor="#FFFFFF">
    <p>Hello,</p>
    <p>it means that the same SUBSCRIBE was aready processed and the
      current one is a retransmission. Can you look at sip network
      traffic (using ngrep, sngrep, ...) and see if there are two
      SUBSCRIBE requests received?</p>
    <p>Cheers,<br>
      Daniel<br>
    </p><div><div class="h5">
    <br>
    <div class="m_225713757218305049moz-cite-prefix">On 05.10.17 11:34, Jack Wang wrote:<br>
    </div>
    </div></div><blockquote type="cite"><div><div class="h5">
      <div dir="ltr">Hello everyone,
        <div><br>
          According to the routing flow set in kamailio.cfg
          <div><br>
          </div>
          <div> # handle retransmissions<br>
          </div>
          <div>
            <div> if(t_precheck_trans()) {</div>
            <div>             t_check_trans();</div>
            <div>             exit;</div>
            <div> }</div>
          </div>
          <div><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;white-space:pre-wrap">t_check_trans()</span><span class="m_225713757218305049gmail-pl-c" style="box-sizing:border-box;color:rgb(106,115,125);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;white-space:pre-wrap"><span class="m_225713757218305049gmail-pl-c" style="box-sizing:border-box">;</span></span><br>
          </div>
          <div><span class="m_225713757218305049gmail-pl-c" style="box-sizing:border-box;color:rgb(106,115,125);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;white-space:pre-wrap"><span class="m_225713757218305049gmail-pl-c" style="box-sizing:border-box">
</span></span></div>
          <div><font face="SFMono-Regular, Consolas, Liberation Mono,
              Menlo, Courier, monospace" color="#000000"><span style="font-size:12px;white-space:pre-wrap">After I traced the flow  it seems that SUBSCRIBE message failed on </span></font><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;white-space:pre-wrap">t_check_trans() and stopped there.</span></div>
          <div><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;white-space:pre-wrap">I add some logs to keep tracing this function and found that:</span></div>
          <div><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,Courier,monospace;font-size:12px;white-space:pre-wrap">
</span></div>
          <div><span style="white-space:pre-wrap">int t_check_trans(struct sip_msg* msg)
{
        struct cell* t;
        int branch;
        int ret;
        
        /* already processing a T */
        if(is_route_type(FAILURE_<wbr>ROUTE)
                        || is_route_type(BRANCH_ROUTE)
                        || is_route_type(BRANCH_FAILURE_<wbr>ROUTE)
                        || is_route_type(TM_ONREPLY_<wbr>ROUTE)) {
                return 1;
        }

        if (msg->first_line.type==SIP_<wbr>REPLY) {
                branch = 0;
                ret = (t_check_msg( msg , &branch)==1) ? 1 : -1;
                tm_ctx_set_branch_index(<wbr>branch);
                return ret;
        } else if (msg->REQ_METHOD==METHOD_<wbr>CANCEL) {
                return w_t_lookup_cancel(msg, 0, 0);
        } else {
                switch(t_check_msg(msg, 0)){
                        case -2: /* possible e2e ack */
                                return 1;
                        case 1: /* found */
                                t=get_t();
                                if (msg->REQ_METHOD==METHOD_ACK){
                                        /* ack to neg. reply  or ack to local trans.
                                           => process it and end the script */
                                        /* FIXME: there's no way to distinguish here 
                                           between acks to local trans. and neg. acks */
                                        if (unlikely(has_tran_tmcbs(t, TMCB_ACK_NEG_IN)))
                                                run_trans_callbacks(TMCB_ACK_<wbr>NEG_IN, t, msg,
                                                                                        0, msg->REQ_METHOD);
                                        t_release_transaction(t);
                                } else {
                                        /* is a retransmission */
                                        if (unlikely(has_tran_tmcbs(t, TMCB_REQ_RETR_IN)))
                                                run_trans_callbacks(TMCB_REQ_<wbr>RETR_IN, t, msg,
                                                                                        0, msg->REQ_METHOD);
                                        t_retransmit_reply(t);
                                }
                                /* no need for UNREF(t); set_t(0) - the end-of-script
                                   t_unref callback will take care of them */
                                return 0; /* exit from the script */</span> <--------------------------<wbr>--
            THE POINT !!<span style="white-space:pre-wrap">
                }
                /* not found or error */
        }
        return -1;
}</span>
          </div>
          <div><br>
          </div>
          <div>If the line "<span style="white-space:pre-wrap">return 0; /* exit from the script */"    was changed to </span>"<span style="white-space:pre-wrap">return 1; /* exit from the script */" , it works ---- means that the configuration script can keep being proceeded now.</span></div>
          <div><span style="white-space:pre-wrap">
</span></div>
          <div><span style="white-space:pre-wrap">Any suggestions?</span></div>
          <div><span style="white-space:pre-wrap">
</span></div>
          <div><span style="white-space:pre-wrap">

</span></div>
        </div>
      </div>
      <br>
      <fieldset class="m_225713757218305049mimeAttachmentHeader"></fieldset>
      <br>
      </div></div><pre>______________________________<wbr>_________________
Kamailio (SER) - Users Mailing List
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<a class="m_225713757218305049moz-txt-link-freetext" href="https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users" target="_blank">https://lists.kamailio.org/<wbr>cgi-bin/mailman/listinfo/sr-<wbr>users</a><span class="HOEnZb"><font color="#888888">
</font></span></pre><span class="HOEnZb"><font color="#888888">
    </font></span></blockquote><span class="HOEnZb"><font color="#888888">
    <br>
    <pre class="m_225713757218305049moz-signature" cols="72">-- 
Daniel-Constantin Mierla
<a class="m_225713757218305049moz-txt-link-abbreviated" href="http://www.twitter.com/miconda" target="_blank">www.twitter.com/miconda</a> -- <a class="m_225713757218305049moz-txt-link-abbreviated" href="http://www.linkedin.com/in/miconda" target="_blank">www.linkedin.com/in/miconda</a>
Kamailio Advanced Training - <a class="m_225713757218305049moz-txt-link-abbreviated" href="http://www.asipto.com" target="_blank">www.asipto.com</a>
Kamailio World Conference - <a class="m_225713757218305049moz-txt-link-abbreviated" href="http://www.kamailioworld.com" target="_blank">www.kamailioworld.com</a></pre>
  </font></span></div>

</blockquote></div><br></div>