}
logger.info("start the replica shards, rebalancing should start, but, only 3 should be rebalancing");
routingNodes = clusterState.routingNodes();
prevRoutingTable = routingTable;
routingTable = strategy.applyStartedShards(clusterState, routingNodes.shardsWithState(INITIALIZING)).routingTable();
clusterState = newClusterStateBuilder().state(clusterState).routingTable(routingTable).build();
routingNodes = clusterState.routingNodes();
// we only allow one relocation at a time
assertThat(routingTable.shardsWithState(STARTED).size(), equalTo(7));