in multi mode, send gratuitous arp
diff --git a/stack.sh b/stack.sh
index 7e4d466..b093616 100755
--- a/stack.sh
+++ b/stack.sh
@@ -603,6 +603,7 @@
 fi
 if [ -n "$MULTI_HOST" ]; then
     add_nova_flag "--multi_host=$MULTI_HOST"
+    add_nova_flag "--send_arp_for_ha=1"
 fi
 
 # Nova Database