阅读本文您会学会&＃xff1a;
1.redis 主从备份并自动切换&＃xff08;master slaver&＃xff09;模式的搭建
2.java 中 配合redis主从备份的方法
【实现目标】&＃xff1a;
master redis 正常运行
slaver redis 自动备份 master 的所有数据
当master redis 冗掉 slaver 自动升级为master 接替原来master 的工作
当原master 重启后 自动加入主从备份&＃xff0c;原master 会变成新的slaver。
【环境配置】&＃xff1a;
此类集群配置需要至少三台机器&＃xff08;当然&＃xff0c;可以是虚拟机&＃xff09;&＃xff0c;三台机器分别安装同样的redis 环境&＃xff0c;并配置好ip&＃xff0c;及port
ip分别为&＃xff1a;

* 192.168.9.17&＃xff08;redis sentinel 集群监控&＃xff09;
* 192.168.9.18&＃xff08;redis 主&＃xff09;
* 192.168.9.19&＃xff08;redis 从&＃xff09;


chmod
【redis 配置】
主&＃xff1a;

* 主的redis 配置文件&＃xff0c;使用默认的配置文件就可以&＃xff0c;当然配置一下更好
* * 此处主要配置的有端口号 port 6379* 后台启动 daemonize yes* 日志位置&＃xff0c;注意要自己新建.log类型文件 logfile"home\oracle\redis\text.log"


从&＃xff1a;

* 从的redis 配置文件
* * 同主的三个配置属性* 增加master 配置 slaveof 192.168.9.18 6379


sentinel&＃xff1a;

* 从安装文件目录下复制 sentinel.conf 文件到软件目录
* 编辑该文件&＃xff0c;可将原来的文件中属性文字等清空&＃xff0c;再加上下列文字


redis-0##sentinel实例之间的通讯端口

port 26379#master1
sentinel monitor master1 192.168.9.18 6379 1
sentinel down-after-milliseconds master1 5000
sentinel failover-timeout master1 900000
sentinel parallel-syncs master1 2

master2 可以添加多组主从的redis监听…….

…
..
..

【启动】

* 一定要按顺序启动redis&＃xff0c;先启动主&＃xff0c;再启动从&＃xff0c;最后启动sentinel
* * ./redis-server ./redis.conf* ./redis-sentinel ./sentinel.conf --sentinel * ps&＃xff1a;如果提示-bash 权限不够 则使用chmod 777 ./redis.conf 这个命令 执行所有需要运行的文件 然后再正常启动就可以了。* 启动后 可以查看redis 的信息
* ./redis-cli -h 192.168.9.18 -p 6379 info 查看redis信息


Replication

role:slave #代表192.168.9.18:6379 这台redis是主
master_host:192.168.9.18
master_port:6379
master_link_status:up
master_last_io_seconds_ago:4
master_sync_in_progress:0
slave_priority:100
slave_read_only:1
connected_slaves:0

* ./redis-cli -h 192.168.9.17 -p 26379 info 查看sentinel 集群信息&＃xff0c;如下则表示配置成功


Sentinel

sentinel_masters:1
sentinel_tilt:0
sentinel_running_scripts:0
sentinel_scripts_queue_length:0
master0:name&＃61;master1,status&＃61;ok,address&＃61;192.168.9.18:6379,slaves&＃61;1,sentinels&＃61;1
【故障演示】

* 主redis 冗掉后 ./redis-cli -h 192.168.9.18 -p 6379 shutdown
* 则发现redis 自动把slaver机器升级为master &＃xff0c;而重新启动原来的master服务&＃xff0c;则原master服务会变成新的slaver。
* 注意&＃xff1a;如果master 发生迁移后&＃xff0c;需要重新启动所有redis 的情况下&＃xff0c;必须最先启动“新的”master节点&＃xff0c;否则sentinel 会一直找不到master。如果想要停止sentinel&＃xff0c;可输入./redis-cli -p 26379 shutdown


【代码处配合自动切换】
上述部分是服务器部分自动切换&＃xff0c;还需要程序处修改redis配置&＃xff0c;此处我们使用jedis 进行演示。
使用以下配置类即可
核心代码在于
Set sentinels &＃61; new HashSet();
// 此处放置ip及端口为 sentinel
// 服务地址&＃xff0c;如果有多个sentinel 则逐一add即可
sentinels.add(“80.27.112.118:26379”);
jedisPool &＃61; new JedisSentinelPool(“master1”,sentinels);
以下代码为工具类 通过配置后可以直接使用

package com.aisino.redis;

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

import com.aisino.spring.util.SystemConfig;

import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;
import redis.clients.jedis.JedisSentinelPool;

public class JedisClusterUtil {

static {// redis 属性配置 startJedisPoolConfig config &＃61; new JedisPoolConfig();config.setMaxTotal(5000);config.setMaxIdle(256);config.setMaxWaitMillis(5000L);config.setTestOnBorrow(true);config.setTestOnReturn(true);config.setTestWhileIdle(true);config.setMinEvictableIdleTimeMillis(60000L);config.setTimeBetweenEvictionRunsMillis(3000L);config.setNumTestsPerEvictionRun(-1);// redis 属性配置 endSet sentinels &＃61; new HashSet();sentinels.add("80.27.112.118:26379"); // 此处放置ip及端口为 sentinel// 服务地址&＃xff0c;如果有多个sentinel 则逐一add即可jedisPool &＃61; new JedisSentinelPool("master1", sentinels, config);
}private static JedisSentinelPool jedisPool;public static String get(String key) {String value &＃61; null;Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();value &＃61; jedis.get(key);} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}return value;
}public static void close(Jedis jedis) {try {jedisPool.returnResource(jedis);} catch (Exception e) {if (jedis.isConnected()) {jedis.quit();jedis.disconnect();}}
}public static byte[] get(byte[] key) {byte[] value &＃61; null;Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();value &＃61; jedis.get(key);} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}return value;
}public static void set(String key, String value) {Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();jedis.set(key, value);} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}
}public static void set(String key, String value, int time) {Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();jedis.set(key, value);jedis.expire(key, time);} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}
}public static void set(byte[] key, byte[] value, int time) {Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();jedis.set(key, value);jedis.expire(key, time);} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}
}public static void hset(byte[] key, byte[] field, byte[] value) {Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();jedis.hset(key, field, value);} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}
}public static void hset(String key, String field, String value) {Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();jedis.hset(key, field, value);} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}
}public static String hget(String key, String field) {String value &＃61; null;Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();value &＃61; jedis.hget(key, field);} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}return value;
}public static byte[] hget(byte[] key, byte[] field) {byte[] value &＃61; null;Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();value &＃61; jedis.hget(key, field);} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}return value;
}public static void hdel(byte[] key, byte[] field) {Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();jedis.hdel(key, new byte[][] { field });} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}
}public static void lpush(String key, String value) {Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();jedis.lpush(key, new String[] { value });} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}
}public static void rpush(byte[] key, byte[] value) {Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();jedis.rpush(key, new byte[][] { value });} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}
}public static void rpoplpush(byte[] key, byte[] destination) {Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();jedis.rpoplpush(key, destination);} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}
}public static List lpopList(byte[] key) {List list &＃61; null;Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();list &＃61; jedis.lrange(key, 0L, -1L);} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}return list;
}public static String rpop(String key) {String bytes &＃61; null;Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();bytes &＃61; jedis.rpop(key);} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}return bytes;
}public static List lrange(byte[] key, int from, int to) {List result &＃61; null;Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();result &＃61; jedis.lrange(key, from, to);} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}return result;
}public static void del(String key) {Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();jedis.del(key);} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}
}public static long llen(byte[] key) {long len &＃61; 0L;Jedis jedis &＃61; null;try {jedis &＃61; jedisPool.getResource();jedis.llen(key);} catch (Exception e) {jedisPool.returnBrokenResource(jedis);e.printStackTrace();} finally {close(jedis);}return len;
}


}