pimd: Add some explanatory debugging for a error condition.

When we decide to ignore a incoming packet, allow detailed
debugging to give a pointer to where to go to understand the
issue.

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>

diff --git a/pimd/pim_mroute.c b/pimd/pim_mroute.c
index 467fc45b985d442e9ef6796692230935e59d6fc9..48890d32fd0a79cb8f93de4584bb072384e0e177 100644 (file)
--- a/pimd/pim_mroute.c
+++ b/pimd/pim_mroute.c
@@ -103,7 +103,12 @@ pim_mroute_msg_nocache (int fd, struct interface *ifp, const struct igmpmsg *msg
       (!pim_ifp) ||
       (!(PIM_I_am_DR(pim_ifp))) ||
       (pim_ifp->itype == PIM_INTERFACE_SSM))
-    return 0;
+    {
+      if (PIM_DEBUG_MROUTE_DETAIL)
+       zlog_debug ("%s: Interface is not configured correctly to handle incoming packet: Could be !DR, !pim_ifp, !SM, !RP",
+                   __PRETTY_FUNCTION__);
+      return 0;
+    }
 
   /*
    * If we've received a multicast packet that isn't connected to