@Override
    public Collection<RedisServer> slaves(NamedNode master) {
        List<Map<String, String>> slaves = connection.sync(StringCodec.INSTANCE, RedisCommands.SENTINEL_SLAVES, master.getName());
        return toRedisServersList(slaves);
    }
@Test
    public void testSlaves() {
        Collection<RedisServer> masters = connection.masters();
        Collection<RedisServer> slaves = connection.slaves(masters.iterator().next());
        assertThat(slaves).hasSize(2);
    }