<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <meta content="text/html; charset=ISO-8859-1"
      http-equiv="Content-Type">
    <title></title>
  </head>
  <body bgcolor="#ffffff" text="#000000">
    <font size="-1"><font face="Courier New, Courier, monospace">Hi, <br>
        <br>
        Just to explain in detail, since I'm a bit puzzled at an
        application<br>
        needing this...NOT doing so creates the potential for breaking a
        lot <br>
        more.<br>
        <br>
        The 503 response is used to indicate to the received that <br>
        <br>
        "I am completely broken, please dont send *anything* to me for a
        while."<br>
        <br>
        A proxy that forwards a 503 response straight through, is
        "telling" <br>
        the previous hop that it should not be used for any request
        whatsoever, <br>
        usually causing that previous hop to blacklist the entire proxy<br>
        for a undefined duration, or according to time specified in the<br>
        Retry-After header. <br>
        In otherwords, the entire proxy becomes dead for all requests
        from<br>
        the previous hop which received the 503. Is that acceptable?<br>
        <br>
        Any application based on proxies relaying 503 responses
        *unmodified*, <br>
        is basing their application logic on something that goes against<br>
        the defined behavior of rfc3261 and seems quite unusual, if not
        dangerous.<br>
        <br>
        That said, if you really, really need it and capable of building<br>
        opensips yourself (which I need and do during my sip
        troubleshooting <br>
        course) it takes 3 seconds to fix by simply opening
        msg_translator.c <br>
        and modifying the line:<br>
        <br>
      </font></font><font size="-1"><font face="Courier New, Courier,
        monospace">if ( msg-&gt;first_line.u.reply.statuscode==503 )</font></font><br>
    <font size="-1"><font face="Courier New, Courier, monospace"><br>
        to <br>
        <br>
      </font></font><font size="-1"><font face="Courier New, Courier,
        monospace">if ( 0 &amp;&amp;
        msg-&gt;first_line.u.reply.statuscode==503 )<br>
        <br>
        and recompiling.<br>
        <br>
        The latest versions even has a "int disable_503_translation =
        0;"<br>
        at the beginning of msg_translator.c, making it even easier to<br>
        disable, although I am very puzzled why you would need this in
        real<br>
        life. I am interested to hear though!<br>
        <br>
        I have checked/seen whether it can be disabled in configuration.<br>
        <br>
        Regards<br>
        Taisto Qvist<br>
        IP-Solutions.se<br>
        <br>
        <br>
        <br>
      </font></font><br>
    thrillerbee skrev 2010-10-07 23:44:
    <blockquote
      cite="mid:AANLkTimQuGBiaY-6JaYzEfBbTYxMH-=OZo5Umm9eohGe@mail.gmail.com"
      type="cite">Bogdan,
      <div><br>
      </div>
      <div>Is this or could this be configurable? &nbsp;It, unfortunately,
        breaks a lot of existing applications.</div>
      <div><br>
      </div>
      <div>Thanks.<br>
        <br>
        <div class="gmail_quote">On Thu, Oct 7, 2010 at 1:15 PM,
          Bogdan-Andrei Iancu <span dir="ltr">&lt;<a
              moz-do-not-send="true"
              href="mailto:bogdan@voice-system.ro">bogdan@voice-system.ro</a>&gt;</span>
          wrote:<br>
          <blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt
            0.8ex; border-left: 1px solid rgb(204, 204, 204);
            padding-left: 1ex;">Hi Julien,<br>
            <br>
            see:<br>
            <a moz-do-not-send="true"
href="http://lists.opensips.org/pipermail/users/2010-September/014505.html"
              target="_blank">http://lists.opensips.org/pipermail/users/2010-September/014505.html</a><br>
            <br>
            Regards,<br>
            Bogdan<br>
            <div>
              <div class="h5"><br>
                Julien Chavanton wrote:<br>
                &gt; Hi, is there any reason why Opensips would replace
                503 with 500 ?<br>
                &gt;<br>
                &gt; The UA initiating the call expect 503 to reroute
                somewhere else<br>
                &gt;<br>
                &gt; INVITE :<br>
                &gt;<br>
                &gt; &nbsp;10.0.20.14(UA) -&gt; 10.2.0.1(Proxy) -&gt;
                10.0.4.202(UA)<br>
                &gt;<br>
                &gt; RESPONSE :<br>
                &gt;<br>
                &gt; U <a moz-do-not-send="true"
                  href="http://10.0.4.202:5060" target="_blank">10.0.4.202:5060</a>
                -&gt; <a moz-do-not-send="true"
                  href="http://10.2.0.1:5060" target="_blank">10.2.0.1:5060</a><br>
                &gt; SIP/2.0 503 Service Unavailable.<br>
                &gt;<br>
                &gt; U <a moz-do-not-send="true"
                  href="http://10.2.0.1:5060" target="_blank">10.2.0.1:5060</a>
                -&gt; <a moz-do-not-send="true"
                  href="http://10.0.20.14:53584" target="_blank">10.0.20.14:53584</a><br>
                &gt; SIP/2.0 500 Service Unavailable.<br>
                &gt;<br>
              </div>
            </div>
            &gt;
            ------------------------------------------------------------------------<br>
            &gt;<br>
            &gt; _______________________________________________<br>
            &gt; Users mailing list<br>
            &gt; <a moz-do-not-send="true"
              href="mailto:Users@lists.opensips.org">Users@lists.opensips.org</a><br>
            &gt; <a moz-do-not-send="true"
              href="http://lists.opensips.org/cgi-bin/mailman/listinfo/users"
              target="_blank">http://lists.opensips.org/cgi-bin/mailman/listinfo/users</a><br>
            &gt;<br>
            <br>
            <br>
            --<br>
            Bogdan-Andrei Iancu<br>
            OpenSIPS Bootcamp<br>
            15 - 19 November 2010, Edison, New Jersey, USA<br>
            <a moz-do-not-send="true" href="http://www.voice-system.ro"
              target="_blank">www.voice-system.ro</a><br>
            <br>
            <br>
            _______________________________________________<br>
            Users mailing list<br>
            <a moz-do-not-send="true"
              href="mailto:Users@lists.opensips.org">Users@lists.opensips.org</a><br>
            <a moz-do-not-send="true"
              href="http://lists.opensips.org/cgi-bin/mailman/listinfo/users"
              target="_blank">http://lists.opensips.org/cgi-bin/mailman/listinfo/users</a><br>
          </blockquote>
        </div>
        <br>
      </div>
      <pre wrap="">
<fieldset class="mimeAttachmentHeader"></fieldset>
_______________________________________________
Users mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Users@lists.opensips.org">Users@lists.opensips.org</a>
<a class="moz-txt-link-freetext" href="http://lists.opensips.org/cgi-bin/mailman/listinfo/users">http://lists.opensips.org/cgi-bin/mailman/listinfo/users</a>
</pre>
    </blockquote>
  </body>
</html>