bgpd: Re-announce the routes if the underlay IGP metric changes

If the underlay IGP metric changes, we SHOULD re-announce the routes with the correct bpi->extra->igpmetric set. Without this patch if the IGP link cost (metric) changes, we never notice this and the peers do not have the updated metrics, which in turn causes incorrect best path selections on remote peers. Signed-off-by: Donatas Abraitis <[email protected]>
FRRouting · Oct 9, 2024 · 5416bfb · 5416bfb
1 parent 07d48af
commit 5416bfb
Showing 1 changed file with 3 additions and 4 deletions.
diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c
@@ -3722,11 +3722,10 @@ static void bgp_process_main_one(struct bgp *bgp, struct bgp_dest *dest,
 
 		/* If there is a change of interest to peers, reannounce the
 		 * route. */
-		if (CHECK_FLAG(old_select->flags, BGP_PATH_ATTR_CHANGED)
-		    || CHECK_FLAG(old_select->flags, BGP_PATH_LINK_BW_CHG)
-		    || CHECK_FLAG(dest->flags, BGP_NODE_LABEL_CHANGED)) {
+		if (CHECK_FLAG(old_select->flags, BGP_PATH_ATTR_CHANGED) ||
+		    CHECK_FLAG(dest->flags, BGP_NODE_LABEL_CHANGED) ||
+		    bgp_zebra_has_route_changed(old_select)) {
 			group_announce_route(bgp, afi, safi, dest, new_select);
-
 			/* unicast routes must also be annouced to
 			 * labeled-unicast update-groups */
 			if (safi == SAFI_UNICAST)