From: Donald Sharp <sharpd@cumulusnetworks.com>
Date: Wed, 20 May 2015 01:04:01 +0000 (-0700)
Subject: The path ordering has an impact on whether paths are flagged as multipath, this shoul... 
X-Git-Tag: frr-2.0-rc1~1430
X-Git-Url: https://git.puffer.fish/?a=commitdiff_plain;h=f4eeff72d5be6c1065f11face168a4bcd832de78;p=mirror%2Ffrr.git

The path ordering has an impact on whether paths are flagged as multipath, this should not be the case.
---

diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c
index 2e572fe757..ef26656aff 100644
--- a/bgpd/bgp_route.c
+++ b/bgpd/bgp_route.c
@@ -1996,8 +1996,6 @@ bgp_best_selection (struct bgp *bgp, struct bgp_node *rn,
             continue;
 
 	new_select = ri1;
-	if (do_mpath)
-	  bgp_mp_list_add (&mp_list, ri1);
 	old_select = CHECK_FLAG (ri1->flags, BGP_INFO_SELECTED) ? ri1 : NULL;
 	if (ri1->next)
 	  for (ri2 = ri1->next; ri2; ri2 = ri2->next)
@@ -2023,24 +2021,13 @@ bgp_best_selection (struct bgp *bgp, struct bgp_node *rn,
 		    {
 		      bgp_info_unset_flag (rn, new_select, BGP_INFO_DMED_SELECTED);
 		      new_select = ri2;
-		      if (do_mpath && !paths_eq)
-			{
-			  bgp_mp_list_clear (&mp_list);
-			  bgp_mp_list_add (&mp_list, ri2);
-			}
 		    }
 
-		  if (do_mpath && paths_eq)
-		    bgp_mp_list_add (&mp_list, ri2);
-
 		  bgp_info_set_flag (rn, ri2, BGP_INFO_DMED_CHECK);
 		}
 	    }
 	bgp_info_set_flag (rn, new_select, BGP_INFO_DMED_CHECK);
 	bgp_info_set_flag (rn, new_select, BGP_INFO_DMED_SELECTED);
-
-	bgp_info_mpath_update (rn, new_select, old_select, &mp_list, mpath_cfg);
-	bgp_mp_list_clear (&mp_list);
       }
 
   /* Check old selected route and new selected route. */
@@ -2080,24 +2067,44 @@ bgp_best_selection (struct bgp *bgp, struct bgp_node *rn,
 
       if (bgp_info_cmp (bgp, ri, new_select, &paths_eq, mpath_cfg))
 	{
-	  if (do_mpath && bgp_flag_check (bgp, BGP_FLAG_DETERMINISTIC_MED))
-	    bgp_mp_dmed_deselect (new_select);
-
 	  new_select = ri;
-
-	  if (do_mpath && !paths_eq)
-	    {
-	      bgp_mp_list_clear (&mp_list);
-	      bgp_mp_list_add (&mp_list, ri);
-	    }
 	}
-      else if (do_mpath && bgp_flag_check (bgp, BGP_FLAG_DETERMINISTIC_MED))
-	bgp_mp_dmed_deselect (ri);
-
-      if (do_mpath && paths_eq)
-	bgp_mp_list_add (&mp_list, ri);
     }
     
+  /* Now that we know which path is the bestpath see if any of the other paths
+   * qualify as multipaths
+   */
+  if (do_mpath && new_select)
+    {
+      for (ri = rn->info; (ri != NULL) && (nextri = ri->next, 1); ri = nextri)
+        {
+          if (ri == new_select)
+            {
+	      bgp_mp_list_add (&mp_list, ri);
+              continue;
+            }
+
+          if (BGP_INFO_HOLDDOWN (ri))
+            continue;
+
+          if (ri->peer &&
+              ri->peer != bgp->peer_self &&
+              !CHECK_FLAG (ri->peer->sflags, PEER_STATUS_NSF_WAIT))
+            if (ri->peer->status != Established)
+              continue;
+
+          if (bgp_flag_check (bgp, BGP_FLAG_DETERMINISTIC_MED)
+              && (! CHECK_FLAG (ri->flags, BGP_INFO_DMED_SELECTED)))
+	      continue;
+
+          bgp_info_cmp (bgp, ri, new_select, &paths_eq, mpath_cfg);
+
+          if (paths_eq)
+            {
+	      bgp_mp_list_add (&mp_list, ri);
+            }
+        }
+    }
 
   if (!bgp_flag_check (bgp, BGP_FLAG_DETERMINISTIC_MED))
     bgp_info_mpath_update (rn, new_select, old_select, &mp_list, mpath_cfg);