diff --git a/ospf6d/ospf6_abr.c b/ospf6d/ospf6_abr.c
index 67d18566ae..7ffb80724b 100644
--- a/ospf6d/ospf6_abr.c
+++ b/ospf6d/ospf6_abr.c
@@ -912,8 +912,9 @@ void ospf6_abr_examin_summary(struct ospf6_lsa *lsa, struct ospf6_area *oa)
 		ospf6_route_merge_nexthops(old, route);
 
 		if (is_debug)
-			zlog_debug("%s: Update route: %s nh count %u",
-				   __PRETTY_FUNCTION__, buf,
+			zlog_debug("%s: Update route: %s old cost %u new cost %u nh count %u",
+				   __PRETTY_FUNCTION__,
+				   buf, old->path.cost, route->path.cost,
 				   listcount(route->nh_list));
 
 		/* Update RIB/FIB */
@@ -924,7 +925,8 @@ void ospf6_abr_examin_summary(struct ospf6_lsa *lsa, struct ospf6_area *oa)
 		ospf6_route_delete(route);
 	} else {
 		if (is_debug)
-			zlog_debug("Install route: %s nh count %u", buf,
+			zlog_debug("%s: Install route: %s cost %u nh count %u",
+				   __PRETTY_FUNCTION__, buf, route->path.cost,
 				   listcount(route->nh_list));
 		/* ospf6_ia_add_nw_route (table, &prefix, route); */
 		ospf6_route_add(route, table);
diff --git a/ospf6d/ospf6_intra.c b/ospf6d/ospf6_intra.c
index c9e2ff9eb5..0b7755a3f4 100644
--- a/ospf6d/ospf6_intra.c
+++ b/ospf6d/ospf6_intra.c
@@ -1631,8 +1631,10 @@ void ospf6_intra_brouter_calculation(struct ospf6_area *oa)
 		brouter_id = ADV_ROUTER_IN_PREFIX(&brouter->prefix);
 		inet_ntop(AF_INET, &brouter_id, brouter_name,
 			  sizeof(brouter_name));
+
 		if (brouter->path.area_id != oa->area_id)
 			continue;
+
 		SET_FLAG(brouter->flag, OSPF6_ROUTE_REMOVE);
 
 		if (IS_OSPF6_DEBUG_BROUTER_SPECIFIC_ROUTER_ID(brouter_id)
@@ -1651,8 +1653,10 @@ void ospf6_intra_brouter_calculation(struct ospf6_area *oa)
 
 		if (brouter->type != OSPF6_DEST_TYPE_LINKSTATE)
 			continue;
+
 		if (ospf6_linkstate_prefix_id(&brouter->prefix) != htonl(0))
 			continue;
+
 		if (!CHECK_FLAG(brouter->path.router_bits, OSPF6_ROUTER_BIT_E)
 		    && !CHECK_FLAG(brouter->path.router_bits,
 				   OSPF6_ROUTER_BIT_B))
@@ -1704,10 +1708,36 @@ void ospf6_intra_brouter_calculation(struct ospf6_area *oa)
 		if (CHECK_FLAG(brouter->flag, OSPF6_ROUTE_WAS_REMOVED))
 			continue;
 
+		/* After iterating spf_table for all routers including
+		 * intra brouter, clear mark for remove flag for
+		 * inter border router if its adv router present in
+		 * SPF table.
+		 */
+		if (brouter->path.type == OSPF6_PATH_TYPE_INTER) {
+			struct prefix adv_prefix;
+
+			ospf6_linkstate_prefix(brouter->path.origin.adv_router,
+					       htonl(0), &adv_prefix);
+
+			if (ospf6_route_lookup(&adv_prefix, oa->spf_table)) {
+				if (IS_OSPF6_DEBUG_BROUTER) {
+					zlog_debug("%s: keep inter brouter %s as adv router 0x%x found in spf",
+						   __PRETTY_FUNCTION__,
+						   brouter_name,
+					brouter->path.origin.adv_router);
+					ospf6_brouter_debug_print(brouter);
+				}
+				UNSET_FLAG(brouter->flag, OSPF6_ROUTE_REMOVE);
+			}
+		}
+
 		if (CHECK_FLAG(brouter->flag, OSPF6_ROUTE_REMOVE)
 		    && CHECK_FLAG(brouter->flag, OSPF6_ROUTE_ADD)) {
 			UNSET_FLAG(brouter->flag, OSPF6_ROUTE_REMOVE);
 			UNSET_FLAG(brouter->flag, OSPF6_ROUTE_ADD);
+			zlog_debug("%s: EVENT unset REOUTE_REMOVE and ROUTE_ADD brouter %s",
+				   __PRETTY_FUNCTION__, brouter_name);
+			ospf6_brouter_debug_print(brouter);
 		}
 
 		if (CHECK_FLAG(brouter->flag, OSPF6_ROUTE_REMOVE)) {
diff --git a/ospf6d/ospf6_route.c b/ospf6d/ospf6_route.c
index 5b36f6300a..87f3f6edca 100644
--- a/ospf6d/ospf6_route.c
+++ b/ospf6d/ospf6_route.c
@@ -719,10 +719,11 @@ struct ospf6_route *ospf6_route_add(struct ospf6_route *route,
 			SET_FLAG(route->flag, OSPF6_ROUTE_BEST);
 			if (IS_OSPF6_DEBUG_ROUTE(MEMORY))
 				zlog_info(
-					"%s %p: route add %p: replacing previous best: %p",
+					"%s %p: route add %p cost %u: replacing previous best: %p cost %u",
 					ospf6_route_table_name(table),
 					(void *)table, (void *)route,
-					(void *)next);
+					route->path.cost,
+					(void *)next, next->path.cost);
 		}
 
 		route->installed = now;
@@ -743,9 +744,9 @@ struct ospf6_route *ospf6_route_add(struct ospf6_route *route,
 
 	/* Else, this is the brand new route regarding to the prefix */
 	if (IS_OSPF6_DEBUG_ROUTE(MEMORY))
-		zlog_debug("%s %p: route add %p %s : brand new route",
+		zlog_debug("%s %p: route add %p %s cost %u: brand new route",
 			   ospf6_route_table_name(table), (void *)table,
-			   (void *)route, buf);
+			   (void *)route, buf, route->path.cost);
 	else if (IS_OSPF6_DEBUG_ROUTE(TABLE))
 		zlog_debug("%s: route add: brand new route",
 			   ospf6_route_table_name(table));