[mpls-linux-devel] A few problems with ldpd

[Scott A. Y. <sy...@im...>]

Hi James. I've been able to get ldpd working quite well with 3 routers in my testbed. Even
the targeted ldp sessions now appear to be working. I have a left LSR, middle, LSR and right LSR. The
targeted session is between the left and right routers.

I've found a few problems and want to get your take on how best to fix them.

1) The xconnect command needs to have the destination IP address stored in host byte order.

--- ldp_vty.c   Tue Mar 25 01:19:59 2008
+++ ldp_vty-new.c       Wed Mar 19 01:55:44 2008
@@ -1618,6 +1618,7 @@
   dest.port = 646;

   VTY_GET_UINT32_RANGE("VCID",vcid,argv[1],0,255);
+  dest.addr.u.ipv4 = ntohl(dest.addr.u.ipv4);

   if (ldp_remote_peer_find(ldp, &dest)) {
     return CMD_WARNING;


2) I found a couple of memory leaks with valgrind:

--- ldp_session.c       Fri Jan  4 23:58:59 2008
+++ ldp_session-new.c       Tue Mar 25 01:25:32 2008
@@ -252,6 +252,8 @@
 {
   LDP_PRINT(NULL, "session delete");
   MPLS_REFCNT_ASSERT(s, 0);
+  ldp_buf_delete(s->tx_buffer);
+  ldp_mesg_delete(s->tx_message);
   mpls_free(s);
 }

--- ldp_buf.c   Tue Mar 25 01:29:01 2008
+++ ldp_buf-new.c       Fri Mar 21 21:18:06 2008
@@ -49,6 +49,8 @@
 void ldp_buf_delete(ldp_buf * b)
 {
   MPLS_ASSERT(b);
+  if (b->buffer)
+    mpls_free(b->buffer);
   mpls_free(b);
 }


These 2 leaks caused ldpd to grow several megabytes per hour on my system.


3) ldpd cannot establish more than 1 session at a time.

I don't know if I have a config error but I keep getting a "ldp_addr_process: session X already advertised this address"
error when the 2nd router attempts to start up a session. I think the address is 127.0.0.1. I tried changing the lsr-id and
transport address but that caused ldpd to crash. The neighbor's status is stuck in the discovery state.

Just to get around this problem and keep going I stuck a return MPLS_SUCCESS in ldpd/ldp_addr.c line 315:

      /* the addr is in the tree */
      if (addr->session) {
        LDP_PRINT(g->user_data,
          "ldp_addr_process: session (%d) already advertised this address\n",
          addr->session->index);
  return MPLS_SUCCESS;
        return MPLS_FAILURE;
      }

Is there something I'm missing with the config to support multiple peers?

Thanks,
Scott Yoder
Support Engineer
ImageStream Internet Solutions, Inc.
E-mail: sy...@im...