mysql5.6安装及主从半同步配置

Posted 2020-11-04

1.安装mysql5.6

rpm -Uvh http://dev.mysql.com/get/mysql-community-release-el7-5.noarch.rpm
yum install mysql-community-server -y
rpm -qa|grep mysql
mysql-community-libs-5.6.40-2.el7.x86_64
mysql-community-server-5.6.40-2.el7.x86_64
mysql-community-release-el7-5.noarch
mysql-community-client-5.6.40-2.el7.x86_64
mysql-community-common-5.6.40-2.el7.x86_64
#到此安装成功

systemctl start mysqld
systemctl enable mysqld
mysql_secure_installation #进行一些安全配置，根据选项选择

2. 主从同步配置

添加my.cnf配置参数

#在主库my.cnf [mysqld]中加入
log-bin = mysql-bin
server-id = 1
#从库
log-bin = mysql-bin
server-id = 2

在主库添加复制账号

grant replication slave on *.* to [email protected]‘192.168.0.%‘ identified by ‘123456‘;

同步主库到从库

(1) 锁表法（锁表的时候不能退出，退出就失效了）

flush table with read lock;       #锁表
mysql> show master status;             #锁表记录的位置点
+------------------+----------+--------------+------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+----------+--------------+------------------+
| mysql-bin.000002 |      253 |              |                  |
+------------------+----------+--------------+------------------+
mysqldump -uroot -p123456 --events -A -B |gzip >/opt/bak_$(date +%F).sql.gz  #比较土的办法加-F 切割binlog可能不对
接着show master status; 如果发现位置一样，则锁表生效，如果不一样说明锁表失败，从库也会文件不同步
unlock tables;    解锁表

(2) 不锁表方法

mysqldump -uroot -p123456 -A -B -F --master-data=2 -x --events|gzip >/opt/all.sql.gz   
show master status; 查看记录的位置点

还原从库

gzip -d bak_xxx.sql.gz    #解压备份的文件
mysql -uroot -p123456  <bak_xxx.sql

配置从库

mysql -uroot -p123456 -S /data/3307/mysql.sock<< EOF
CHANGE MASTER TO  
MASTER_HOST=‘10.0.0.52‘, 
MASTER_PORT=3306,
MASTER_USER=‘rep‘, 
MASTER_PASSWORD=‘123456‘, 
MASTER_LOG_FILE=‘mysql-bin.000002‘,
MASTER_LOG_POS=253; 
EOF

start slave;   #开始同步在从库使用 
show slave status\G   出现如下信息成功
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
       Seconds_Behind_Master: 0   #这个是从库落后主库的秒数 不是很准

3. 半同步复制配置

3.1 安装插件

#这是半同步所需的插件
ll -h /usr/lib64/mysql/plugin/semisync_*
-rwxr-xr-x. 1 root root 509K Feb 26 21:27 /usr/lib64/mysql/plugin/semisync_master.so
-rwxr-xr-x. 1 root root 273K Feb 26 21:27 /usr/lib64/mysql/plugin/semisync_slave.so
#主库加载插件
mysql> INSTALL PLUGIN rpl_semi_sync_master SONAME ‘semisync_master.so‘;
mysql> set global rpl_semi_sync_master_enabled=on;
#从库加载插件
mysql>  INSTALL PLUGIN rpl_semi_sync_slave SONAME ‘semisync_slave.so‘;
mysql> set global rpl_semi_sync_slave_enabled=on;

3.2 加入my.cnf参数

#主库[mysqld]加入下面参数
rpl_semi_sync_master_enabled = 1  
#从库[mysqld]加入下面参数
rpl_semi_sync_slave_enabled = 1  

查看参数

show variables like ‘%Rpl%‘;

3.3 验证

show global status like ‘rpl_semi%‘;
+--------------------------------------------+-------+
| Variable_name                              | Value |
+--------------------------------------------+-------+
| Rpl_semi_sync_master_clients               | 1     |
| Rpl_semi_sync_master_net_avg_wait_time     | 0     |
| Rpl_semi_sync_master_net_wait_time         | 0     |
| Rpl_semi_sync_master_net_waits             | 0     |
| Rpl_semi_sync_master_no_times              | 0     |
| Rpl_semi_sync_master_no_tx                 | 0     |
| Rpl_semi_sync_master_status                | ON    |
| Rpl_semi_sync_master_timefunc_failures     | 0     |
| Rpl_semi_sync_master_tx_avg_wait_time      | 0     |
| Rpl_semi_sync_master_tx_wait_time          | 0     |
| Rpl_semi_sync_master_tx_waits              | 0     |
| Rpl_semi_sync_master_wait_pos_backtraverse | 0     |
| Rpl_semi_sync_master_wait_sessions         | 0     |
| Rpl_semi_sync_master_yes_tx                | 0     |
+--------------------------------------------+-------+

mysql> show global status like ‘rpl_semi%‘;   
+----------------------------+-------+
| Variable_name              | Value |
+----------------------------+-------+
| Rpl_semi_sync_slave_status | ON    |
+----------------------------+-------+

4 测试