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    <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>
    <br>
    <div class="moz-cite-prefix">On 05.10.17 11:34, Jack Wang wrote:<br>
    </div>
    <blockquote type="cite"
cite="mid:CAJwNTAQRvfF1zmJ9WNcHP2Ni5n43pmGWupjE9eHQbOA=k_krjQ@mail.gmail.com">
      <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">t_check_trans()</span><span class="gmail-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"><span class="gmail-pl-c" style="box-sizing:border-box">;</span></span><br>
          </div>
          <div><span class="gmail-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"><span class="gmail-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">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">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">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">
</span></div>
          <div><span style="white-space:pre">int t_check_trans(struct sip_msg* msg)
{
        struct cell* t;
        int branch;
        int ret;
        
        /* already processing a T */
        if(is_route_type(FAILURE_ROUTE)
                        || is_route_type(BRANCH_ROUTE)
                        || is_route_type(BRANCH_FAILURE_ROUTE)
                        || is_route_type(TM_ONREPLY_ROUTE)) {
                return 1;
        }

        if (msg->first_line.type==SIP_REPLY) {
                branch = 0;
                ret = (t_check_msg( msg , &branch)==1) ? 1 : -1;
                tm_ctx_set_branch_index(branch);
                return ret;
        } else if (msg->REQ_METHOD==METHOD_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_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_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> <----------------------------
            THE POINT !!<span style="white-space:pre">
                }
                /* not found or error */
        }
        return -1;
}</span>
          </div>
          <div><br>
          </div>
          <div>If the line "<span style="white-space:pre">return 0; /* exit from the script */"    was changed to </span>"<span style="white-space:pre">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">
</span></div>
          <div><span style="white-space:pre">Any suggestions?</span></div>
          <div><span style="white-space:pre">
</span></div>
          <div><span style="white-space:pre">

</span></div>
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      <br>
      <pre wrap="">_______________________________________________
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</pre>
    </blockquote>
    <br>
    <pre class="moz-signature" cols="72">-- 
Daniel-Constantin Mierla
<a class="moz-txt-link-abbreviated" href="http://www.twitter.com/miconda">www.twitter.com/miconda</a> -- <a class="moz-txt-link-abbreviated" href="http://www.linkedin.com/in/miconda">www.linkedin.com/in/miconda</a>
Kamailio Advanced Training - <a class="moz-txt-link-abbreviated" href="http://www.asipto.com">www.asipto.com</a>
Kamailio World Conference - <a class="moz-txt-link-abbreviated" href="http://www.kamailioworld.com">www.kamailioworld.com</a></pre>
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