RedisCluster集群模式下master宕機主從切換期間Lettuce連接Redis無法使用報錯Redis command timed out的問題

 

錯誤：

 

 

 

 

原因：

SpringBoot2.X版本開始Redis默認的連接池都是采用的Lettuce。當節點發生改變后，Letture默認是不會刷新節點拓撲的。

 

 

方案一：把lettuce換成jedis

只需要在pom.xml里調整一下依賴的引用

  <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
            <version>2.1.5.RELEASE</version>
                <!-- 不用lettuce ,用jedis -->
                <exclusions>
                    <exclusion>
                        <groupId>io.lettuce</groupId>
                        <artifactId>lettuce-core</artifactId>
                    </exclusion>
                </exclusions>
        </dependency>


        <dependency>
            <groupId>redis.clients</groupId>
            <artifactId>jedis</artifactId>
            <version>3.1.0-m4</version>
        </dependency>

 

方案二：刷新節點拓撲視圖

redis節點異常，服務端的Redis集群拓撲被刷新了，java程序沒有獲取到新的拓撲。

Lettuce官方文檔中關於Redis Cluster的相關說明：Lettuce處理Moved和Ask永久重定向，由於命令重定向，你必須刷新節點拓撲視圖。而自適應拓撲刷新（Adaptive updates）與定時拓撲刷新（Periodic updates）是默認關閉的，可以通過如下代碼打開。

 

代碼如下：

package com.montnets.common.redis;

import io.lettuce.core.ClientOptions;
import io.lettuce.core.cluster.ClusterClientOptions;
import io.lettuce.core.cluster.ClusterTopologyRefreshOptions;
import org.apache.commons.pool2.impl.GenericObjectPoolConfig;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.data.redis.RedisProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.data.redis.connection.RedisClusterConfiguration;
import org.springframework.data.redis.connection.RedisNode;
import org.springframework.data.redis.connection.RedisPassword;
import org.springframework.data.redis.connection.lettuce.LettuceClientConfiguration;
import org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory;
import org.springframework.data.redis.connection.lettuce.LettucePoolingClientConfiguration;
import org.springframework.stereotype.Component;

import java.time.Duration;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

/**
 * @author : harara
 * @version : 2.0
 * @date : 2020/7/27 10:19
 */
@Component
public class RedisPoolConfig {

    @Autowired
    private RedisProperties redisProperties;

    public GenericObjectPoolConfig<?> genericObjectPoolConfig(RedisProperties.Pool properties) {
        GenericObjectPoolConfig<?> config = new GenericObjectPoolConfig<>();
        config.setMaxTotal(properties.getMaxActive());
        config.setMaxIdle(properties.getMaxIdle());
        config.setMinIdle(properties.getMinIdle());
        if (properties.getTimeBetweenEvictionRuns() != null) {
            config.setTimeBetweenEvictionRunsMillis(properties.getTimeBetweenEvictionRuns().toMillis());
        }
        if (properties.getMaxWait() != null) {
            config.setMaxWaitMillis(properties.getMaxWait().toMillis());
        }
        return config;
    }

    @Bean(destroyMethod = "destroy")
    public LettuceConnectionFactory lettuceConnectionFactory() {

        //開啟 自適應集群拓撲刷新和周期拓撲刷新
        ClusterTopologyRefreshOptions clusterTopologyRefreshOptions =  ClusterTopologyRefreshOptions.builder()
                // 開啟全部自適應刷新
                .enableAllAdaptiveRefreshTriggers() // 開啟自適應刷新,自適應刷新不開啟,Redis集群變更時將會導致連接異常
                // 自適應刷新超時時間(默認30秒)
                .adaptiveRefreshTriggersTimeout(Duration.ofSeconds(30)) //默認關閉開啟后時間為30秒
                // 開周期刷新
                .enablePeriodicRefresh(Duration.ofSeconds(20))  // 默認關閉開啟后時間為60秒 ClusterTopologyRefreshOptions.DEFAULT_REFRESH_PERIOD 60  .enablePeriodicRefresh(Duration.ofSeconds(2)) = .enablePeriodicRefresh().refreshPeriod(Duration.ofSeconds(2))
                .build();

        // https://github.com/lettuce-io/lettuce-core/wiki/Client-Options
        ClientOptions clientOptions = ClusterClientOptions.builder()
                .topologyRefreshOptions(clusterTopologyRefreshOptions)
                .build();

        LettuceClientConfiguration clientConfig = LettucePoolingClientConfiguration.builder()
                .poolConfig(genericObjectPoolConfig(redisProperties.getJedis().getPool()))
                //.readFrom(ReadFrom.MASTER_PREFERRED)
                .clientOptions(clientOptions)
                .commandTimeout(redisProperties.getTimeout()) //默認RedisURI.DEFAULT_TIMEOUT 60
                .build();

        List<String> clusterNodes = redisProperties.getCluster().getNodes();
        Set<RedisNode> nodes = new HashSet<RedisNode>();
        clusterNodes.forEach(address -> nodes.add(new RedisNode(address.split(":")[0].trim(), Integer.valueOf(address.split(":")[1]))));

        RedisClusterConfiguration clusterConfiguration = new RedisClusterConfiguration();
        clusterConfiguration.setClusterNodes(nodes);
        clusterConfiguration.setPassword(RedisPassword.of(redisProperties.getPassword()));
        clusterConfiguration.setMaxRedirects(redisProperties.getCluster().getMaxRedirects());

        LettuceConnectionFactory lettuceConnectionFactory = new LettuceConnectionFactory(clusterConfiguration, clientConfig);
        // lettuceConnectionFactory.setShareNativeConnection(false); //是否允許多個線程操作共用同一個緩存連接，默認true，false時每個操作都將開辟新的連接
        // lettuceConnectionFactory.resetConnection(); // 重置底層共享連接, 在接下來的訪問時初始化
        return lettuceConnectionFactory;
    }
}

 

 

參考地址：

RedisCluster集群模式下master宕機主從切換期間Lettuce連接Redis無法使用報錯Redis command timed out的問題 : https://blog.csdn.net/u010046887/article/details/106948341