diff --git a/tests/TestRunner/tmp_multi_cluster.py b/tests/TestRunner/tmp_multi_cluster.py
index 2edcef29de..f3d3efe803 100755
--- a/tests/TestRunner/tmp_multi_cluster.py
+++ b/tests/TestRunner/tmp_multi_cluster.py
@@ -54,7 +54,7 @@ if __name__ == '__main__':
 	clusters = []
 	for c in range(1,num_clusters+1):
 		# now start the cluster up
-		local_c = TempCluster(args.build_dir, port="{}501".format(c))
+		local_c = TempCluster(args.build_dir, 1, port="{}501".format(c))
 
 		local_c.__enter__()
 		clusters.append(local_c)