Hi all,
I want to configure SER and SEMS using two different instances of SER like:
 
[SER A]<--IP interface-->[SER B]<=fifo interface=>[SEMS]
Both SER instaces and SEMS are located in the same machine.
In the SER-SEMS-HOWTO there's an explanation on how to redirect SIP messages to SEMS:
MY QUESTION IS, WHERE DO THESE LINES HAVE TO BE ADDED, IN THE SER_A.CFG OR THE SER_B.CFG  ( I would then change the configuration to use fifo instead of unix sockets). This is a very simple question but it will help a lot.
Thank you, Llanos
 
EXTRACT FROM SER-SEMS-HOWTO:
2.2.3 Redirecting SIP messages to Sems:
    - add following lines to your ser.cfg where you need to redirect the call:
      # select messages to redirect:
      if ( method=="ACK" || method=="INVITE" || method=="BYE" ||
           method=="CANCEL" ){
           # switch to stateful mode:
           if (!t_newtran()){
                sl_send_reply("500","could not create transaction");
                break;
           };
           # prevent timeout on the other side:
           t_reply("100","Trying - just wait a minute !");
          
           if (method=="INVITE"){
                # redirect the call to the 'conference' plug-in
                # if the URI begin with 100
                if (uri=~"sip:100.*@") {
                   # assumes that Sems configuration parameter 'socket_name='
                   # has been set to /tmp/am_sock
                   if(!t_write_unix("/tmp/am_sock","conference")) {
                      t_reply("500","error contacting sems");
                   };
                   break;
                };
                # redirect the call to the 'announcement' plug-in
                # if the URI begin with 200
                if (uri=~"sip:200.*@") {
                   if(!t_write_unix("/tmp/am_sock","announcement")) {
                      t_reply("500","error contacting sems");
                   };
                   break;
                };
                # no service number, redirect to voicemail.
                # do not forget to load AVPs so that voicemail gets the
                # callee's email address.
                load_avp("ruri","email",0);
                if(!t_write_unix("/tmp/am_sock","voicemail")) {
                    t_reply("500","error contacting sems");
                };
                break;
           }
           else if (method=="BYE" || method="CANCEL") {
                # Sems should already know which plug-in is handling that
                # call. "bye" is no plug-in name. It is a reserved name which
                # tells Sems to terminate the call.
                if(!t_write_unix("/tmp/am_sock","bye")) {
                    t_reply("500","error contacting sems");
                };
           };
      };