关掉其中的一个master,集群会自动分配

redis-cli --cluster check 127.0.0.1:7000

2、脚本创建

生成集群

cd /root/redis-6.2.1/utils/create-cluster
./create-cluster start

./create-cluster create

五、redis结合MySQL

1.mySQL与redis不实时同步

需要三台主机，由于前面的实验server2成为了master，其余节点变为slave

server1,3中查看系统文件

vim .bash_PRofile
source .bash_profile

/etc/init.d/mysqld stop
yum install -y mariadb-server

修改配置文件,启动

vim /etc/my.cnf
systemctl start mariadb

vim test.sql

use test;
CREATE TABLE `test` (`id` int(7) NOT NULL AUTO_INCREMENT, `name` char(8) DEFAULT NULL, Primary KEY (`id`)) ENginE=InnoDB DEFAULT CHARSET=utf8;
INSERT INTO `test` VALUES (1,'test1'),(2,'test2'),(3,'test3'),(4,'test4'),(5,'test5'),(6,'test6'),(7,'test7'),(8,'test8'),(9,'test9');

#DELIMITER $$
#CREATE TRIGGER datatoredis AFTER UPDATE ON test FOR each ROW BEGIN
#    SET @recv=gman_do_background('syncToRedis', json_object(NEW.id as `id`, NEW.name as `name`));
#  END$$
#DELIMITER ;

mysql < test.sql 

使用该数据库

在server1中，安装php-FPM （需从网上下载）httpd psmisc

yum install -y php-fpm httpd psmic
cd /etc/php-fpm.d/

关闭上次实验开启的集群

killall redis-server

<?php
        $redis = new Redis();
        $redis->connect('172.25.34.2',6379) or die ("could net connect redis server");
  #      $query = "select * From test limit 9";
        $query = "select * from test";
        for ($key = 1; $key < 10; $key++)
        {
                if (!$redis->get($key))
                {
                        $connect = mysql_connect('172.25.34.3','redis','westos');
                        mysql_select_db(test);
                        $result = mysql_query($query);
                        //如果没有找到$key,就将该查询sql的结果缓存到redis
                        while ($row = mysql_fetch_assoc($result))
                        {
                                $redis->set($row['id'],$row['name']);
                        }
                        $myserver = ';mysql';
                        break;
                }
                else
                {
                        $myserver = "redis";
                        $data[$key] = $redis->get($key);
                }
        }

        echo $myserver;
        echo "<br>";
        for ($key = 1; $key < 10; $key++)
        {
                echo "number is <b><font color=#FF0000>$key</font></b>";

                echo "<br>";

                echo "name is <b><font color=#FF0000>$data[$key]</font></b>";

                echo "<br>";
        }
?>

server3授权

 grant all on test.* to redis@'%' identified by 'westos';

server2的redis中，同步数据

2.配置gearman实现mysql与redis实时同步

gearman是支持分布式任务分发的框架，运行在后台

在server3上gearman安装步骤： 准备lib_mysqluDF_json-master.zip文件，解压并进入解压后的目录

unzip lib_mysqludf_json-master.zip
cd lib_mysqludf_json-master/

安装mariadb开发包

yum install -y mariadb-devel

重新编译

gcc $(mysql_config --CFlags) -shared -fPIC -o lib_mysqludf_json.so lib_mysqludf_json.c

cp lib_mysqludf_json.so /usr/lib64/mysql/plugin/

模块目录可在数据库查看

cp lib_mysqludf_json.so /usr/lib64/mysql/plugin/

 CREATE FUNCTION json_object RETURNS STRING SONAME 'lib_mysqludf_json.so';

server1中，安装gearman，开启并查看端口

systemctl start gearmand
netstat -antlp|grep :4730

tar zxf gearman-mysql-udf-0.6.tar.gz
cd gearman-mysql-udf-0.6/
./configure --libdir=/usr/lib64/plugin

发现需要依赖性

./configure --libdir=/usr/lib64/plugin --with-mysql=/usr/bin/mysql_config
make && make install

进入mysql

CREATE FUNCTION gman_do_background RETURNS STRING SONAME 'libgearman_mysql_udf.so';
CREATE FUNCTION gman_servers_set RETURNS STRING SONAME 'libgearman_mysql_udf.so';

vim test.sql

use test;
DELIMITER $$
CREATE TRIGGER datatoredis AFTER UPDATE ON test FOR EACH ROW BEGIN
    SET @RECV=gman_do_background('syncToRedis', json_object(NEW.id as `id`, NEW.name as `name`)); 
  END$$
DELIMITER ;

mysql < test.sql

进入数据库查看触发器

SHOW TRIGGERS FROM test;

SHOW TRIGGERS FROM testG;

<?php
$worker = new GearmanWorker();
$worker->addServer();
$worker->addFunction('syncToRedis', 'syncToRedis');

$redis = new Redis();
$redis->connect('172.25.34.2', 6379);

while($worker->work());
function syncToRedis($job)
{
        global $redis;
        $workString = $job->workload();
        $work = json_decode($workString);
        if(!isset($work->id)){
                return false;
        }
        $redis->set($work->id, $work->name);
}
?>

打入后台运行

nohup php worker.php &

use test;
update test set name='redhat' where id=1;

进入网页查看更新