diff --git a/include/types/server.h b/include/types/server.h
index ce138206b..5d8921282 100644
--- a/include/types/server.h
+++ b/include/types/server.h
@@ -203,6 +203,7 @@ struct server {
 	unsigned wscore;			/* weight score, used during srv map computation */
 	unsigned prev_eweight;			/* eweight before last change */
 	unsigned rweight;			/* remainer of weight in the current LB tree */
+	unsigned cumulative_weight;		/* weight of servers prior to this one in the same group, for chash balancing */
 	unsigned npos, lpos;			/* next and last positions in the LB tree */
 	struct eb32_node lb_node;               /* node used for tree-based load balancing */
 	struct eb_root *lb_tree;                /* we want to know in what tree the server is */
diff --git a/src/backend.c b/src/backend.c
index faf872c0b..573f054dc 100644
--- a/src/backend.c
+++ b/src/backend.c
@@ -115,9 +115,11 @@ void recount_servers(struct proxy *px)
 			    !(px->options & PR_O_USE_ALL_BK))
 				px->lbprm.fbck = srv;
 			px->srv_bck++;
+			srv->cumulative_weight = px->lbprm.tot_wbck;
 			px->lbprm.tot_wbck += srv->eweight;
 		} else {
 			px->srv_act++;
+			srv->cumulative_weight = px->lbprm.tot_wact;
 			px->lbprm.tot_wact += srv->eweight;
 		}
 	}