FIB path preference

Paths are given a preference, lowest value is 'best'. Only paths that are up are up contribute to fprwarding - that's unchanged. What's new is that of the path's that re up only those that have the best preference contribute. A poor man's primary and backup. It's not true primary/backup function because the FIB must converge before the lower preference paths are used.

Change-Id: Ie4453c4a7b1094c6c2b51fe1594b8302103bb68e
Signed-off-by: Neale Ranns <nranns@cisco.com>

1 files changed, 11 insertions, 20 deletions

diff --git a/src/vnet/ip/lookup.c b/src/vnet/ip/lookup.c
index 6547cad51b1..533d010a738 100755
--- a/src/vnet/ip/lookup.c
+++ b/src/vnet/ip/lookup.c
@@ -360,6 +360,7 @@ vnet_ip_route_cmd (vlib_main_t * vm,
   fib_prefix_t *prefixs = NULL, pfx;
   mpls_label_t out_label, via_label;
   clib_error_t *error = NULL;
+  u32 weight, preference;
   u32 table_id, is_del;
   vnet_main_t *vnm;
   u32 fib_index;
@@ -441,26 +442,6 @@ vnet_ip_route_cmd (vlib_main_t * vm,
 	  pfx.fp_proto = FIB_PROTOCOL_IP6;
 	  vec_add1 (prefixs, pfx);
 	}
-      else if (unformat (line_input, "via %U %U weight %u",
-			 unformat_ip4_address,
-			 &rpath.frp_addr.ip4,
-			 unformat_vnet_sw_interface, vnm,
-			 &rpath.frp_sw_if_index, &rpath.frp_weight))
-	{
-	  rpath.frp_proto = FIB_PROTOCOL_IP4;
-	  vec_add1 (rpaths, rpath);
-	}
-
-      else if (unformat (line_input, "via %U %U weight %u",
-			 unformat_ip6_address,
-			 &rpath.frp_addr.ip6,
-			 unformat_vnet_sw_interface, vnm,
-			 &rpath.frp_sw_if_index, &rpath.frp_weight))
-	{
-	  rpath.frp_proto = FIB_PROTOCOL_IP6;
-	  vec_add1 (rpaths, rpath);
-	}
-
       else if (unformat (line_input, "via %U %U",
 			 unformat_ip4_address,
 			 &rpath.frp_addr.ip4,
@@ -482,6 +463,16 @@ vnet_ip_route_cmd (vlib_main_t * vm,
 	  rpath.frp_proto = FIB_PROTOCOL_IP6;
 	  vec_add1 (rpaths, rpath);
 	}
+      else if (unformat (line_input, "weight %u", &weight))
+	{
+	  ASSERT (vec_len (rpaths));
+	  rpaths[vec_len (rpaths) - 1].frp_weight = weight;
+	}
+      else if (unformat (line_input, "preference %u", &preference))
+	{
+	  ASSERT (vec_len (rpaths));
+	  rpaths[vec_len (rpaths) - 1].frp_preference = preference;
+	}
       else if (unformat (line_input, "via %U next-hop-table %d",
 			 unformat_ip4_address,
 			 &rpath.frp_addr.ip4, &rpath.frp_fib_index))