SpringBoot2.x开始默认使用的Redis客户端由Jedis变成了Lettuce，但是当Redis集群中某个节点挂掉之后，Lettuce将无法继续操作Redis，原因在于此时Lettuce使用的仍然是有问题的连接信息。

实际上，Lettuce支持redis 集群拓扑动态刷新，但是默认并没有开启，SpringBoot在集成Lettuce时默认也没有开启。并且在SpringBoot2.3.0之前，是没有配置项设置Lettuce自动刷新拓扑的。

相关issue：Add configuration to enable Redis Cluster topology refresh

解决方案1：

1. 升级到SpringBoot2.3.0或以上版本。并添加如下配置项

spring.redis.timeout=60s
spring.redis.lettuce.cluster.refresh.period=60s
spring.redis.lettuce.cluster.refresh.adaptive=true

解决方案2：
配置LettuceConnectionFactory ，设置拓扑刷新策略。

@Bean
public DefaultClientResources lettuceClientResources() {
    
    
    return DefaultClientResources.create();
}

@Bean
public LettuceConnectionFactory lettuceConnectionFactory(RedisProperties redisProperties, ClientResources clientResources) {
    
    

    ClusterTopologyRefreshOptions topologyRefreshOptions = ClusterTopologyRefreshOptions.builder()
            .enablePeriodicRefresh(Duration.ofSeconds(30)) //按照周期刷新拓扑
            .enableAllAdaptiveRefreshTriggers() //根据事件刷新拓扑
            .build();

    ClusterClientOptions clusterClientOptions = ClusterClientOptions.builder()
            //redis命令超时时间,超时后才会使用新的拓扑信息重新建立连接
            .timeoutOptions(TimeoutOptions.enabled(Duration.ofSeconds(10)))
            .topologyRefreshOptions(topologyRefreshOptions)
            .build();

    LettuceClientConfiguration clientConfiguration = LettuceClientConfiguration.builder()
            .clientResources(clientResources)
            .clientOptions(clusterClientOptions)
            .build();

    RedisClusterConfiguration clusterConfig = new RedisClusterConfiguration(redisProperties.getCluster().getNodes());
    clusterConfig.setMaxRedirects(redisProperties.getCluster().getMaxRedirects());
    clusterConfig.setPassword(RedisPassword.of(redisProperties.getPassword()));

    LettuceConnectionFactory lettuceConnectionFactory = new LettuceConnectionFactory(clusterConfig, clientConfiguration);

    return lettuceConnectionFactory;
}

解决方案3:

1. 将spring-boot-starter-data-redis依赖的Lettuce，修改成Jedis。

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-redis</artifactId>
    <exclusions>
        <exclusion>
            <groupId>io.lettuce</groupId>
            <artifactId>lettuce-core</artifactId>
        </exclusion>
    </exclusions>
</dependency>
<dependency>
    <groupId>redis.clients</groupId>
    <artifactId>jedis</artifactId>
</dependency>