mysql高级知识之集群

一、安装

        源码编译MySQL,若需要MySQLtar包可私信我

#创建数据目录
mkdir /data/mysql -p#安装相关依赖
yum install libtirpc-devel-0.2.4-0.16.el7.x86_64.rpm
yum install cmake gcc-c++ openssl-devel ncurses-devel.x86_64 libtirpc-devel-1.3.3-8.el9_4.x86_64.rpm rpcgen.x86_64 -y#解压MySQL包，并进入其目录
tar zxf mysql-boost-5.7.44.tar.gz
cd mysql-5.7.44/#进行源码安装
cmake -DCMAKE_INSTALL_PREFIX=/usr/local/mysql -DMYSQL_DATADIR=/data/mysql -DMYSQL_UNIX_ADDR=/data/mysql/mysql.sock -DWITH_INNOBASE_STORAGE_ENGINE=1 \
-DWITH_EXTRA_CHARSETS=all -DDEFAULT_CHARSET=utf8mb4 -DDEFAULT_COLLATION=utf8mb4_unicode_ci -DWITH_BOOST=/root/mysql-5.7.44/boost/boost_1_59_0/#有几个核就j几
make -j2#安装
make install#拷贝启动文件
cp /usr/local/mysql/support-files/mysql.server /etc/init.d/#修改配置文件
vim /etc/my.cnf
[mysqld]	
datadir=/data/mysql
socket=/data/mysql/mysql.sock
symbolic-links=0#设置环境变量
vim ~/.bash_profile
PATH=$PATH:$HOME/bin:/usr/local/mysql/bin
source ~/.bash_profile#建立mysql用户
useradd -s /sbin/nologin -M mysql#将mysql数据目录归属于mysql用户
chown mysql.mysql -R /data/mysql/#清空数据目录，注意非实验环境需先备份其中内容
rm -rf /data/mysql/*#MySQL初始化，注意初始化之后会产生一个临时密码，在第一次登陆后需改密码
mysqld --user mysql --initialize#登录MySQL，并修改root密码，第一次登录不修改密码使用不了
mysql -uroot -p'j;t/EZJ*g1y7'
alter user root@localhost identified by 'Mysql@123';#设置MySQL开机自启动
yum install chkconfig -y
chkconfig mysqld on ###不设定启动级别，默认2345
chkconfig --list

在三台主机上安装MySQL，具体如下 

 二、主从复制

1、干净数据库主从复制

步骤如下

        1）分别在主库从库设定不同的server-id以区分不同的数据库
        注：设定server-id后从机设定了read_only=1也可以写入，在设定server-id之后不让从机写入需设定super_read_only=on

        2）设定数据库开始二进制日志

        3）在主库上创建主从复制的用户，并给予权限

        4）配置从库

#主库node1--配置server-id和开启二进制日志（注，修改完配置文件需要重启数据库）
vim /etc/my.cnf
[mysqld]
datadir=/data/mysql
socket=/data/mysql/mysql.sock
symbolic-links=0
server-id=1            #server-id
log-bin=mysql-bin      #二进制日志#主库--创建用户并授权（登录数据库自己解决）
create user repl@'%' identified by 'Mysql@123';        #创建用户
grant replication slave on *.* to repl@'%';            #授权#配置完成之后可查看master状态
mysql> show master status ;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000001 |      595 |              |                  |                   |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)#从库node2--配置server-id和开启二进制日志（注，修改完配置文件需要重启数据库）
vim /etc/my.cnf
[mysqld]
datadir=/data/mysql
socket=/data/mysql/mysql.sock
symbolic-links=0
server-id=2            #server-id
log-bin=mysql-bin      #二进制日志#从库node2--配置主从
change master to master_host='192.168.220.10',master_user='repl',master_password='Mysql@123',master_log_file='mysql-bin.000001',master_log_pos=595;
start slave;#可以查看slave状态
mysql> show slave status\G;
*************************** 1. row ***************************Slave_IO_State: Waiting for master to send eventMaster_Host: 192.168.220.10Master_User: replMaster_Port: 3306Connect_Retry: 60Master_Log_File: mysql-bin.000001Read_Master_Log_Pos: 595Relay_Log_File: node2-relay-bin.000002Relay_Log_Pos: 320Relay_Master_Log_File: mysql-bin.000001Slave_IO_Running: Yes        #看到IO线程YesSlave_SQL_Running: Yes        #看到SQL线程Yes则说明主从配置成功

2、有数据的数据库主从复制

步骤如下

        1）分别在主库从库设定不同的server-id以区分不同的数据库
        注：设定server-id后从机设定了read_only=1也可以写入，在设定server-id之后不让从机写入需设定super_read_only=on

        2）设定数据库开始二进制日志

        3）在主库上创建主从复制的用户，并给予权限

        4）导出主库数据，传到从库做还原

        注：在企业搭建主从复制拉平数据时，需要先将主库锁起来

        5）配置从库

#主库node1--配置server-id和开启二进制日志（注，修改完配置文件需要重启数据库）
vim /etc/my.cnf
[mysqld]
datadir=/data/mysql
socket=/data/mysql/mysql.sock
symbolic-links=0
server-id=1            #server-id
log-bin=mysql-bin      #二进制日志#主库--创建用户并授权（登录数据库自己解决）
create user repl@'%' identified by 'Mysql@123';        #创建用户
grant replication slave on *.* to repl@'%';            #授权#配置完成之后可查看master状态
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000001 |     1481 |              |                  |                   |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)#主库和从库之间拉平数据，主库要先锁表
mysql> flush tables with read lock;
Query OK, 0 rows affected (0.00 sec)#验证表是否锁住
mysql> insert into db1.tb1 values('3','力迅');
ERROR 1223 (HY000): Can't execute the query because you have a conflicting read lock#导出主库数据（注：企业中不能将数据库密码显示输入）
mysqldump -uroot -p'Mysql@123' -B db1 > mysql.sql#将sql传至新的node节点
scp /root/mysql.sql root@node3:/root#从库node3--配置server-id和开启二进制日志（注，修改完配置文件需要重启数据库）
vim /etc/my.cnf
[mysqld]
datadir=/data/mysql
socket=/data/mysql/mysql.sock
symbolic-links=0
server-id=3            #server-id
log-bin=mysql-bin      #二进制日志#从库导入主库数据（注：需要先登录数据库）
mysql> source /root/mysql.sql#从库node3--配置主从
change master to master_host='192.168.220.10',master_user='repl',master_password='Mysql@123',master_log_file='mysql-bin.000001',master_log_pos=595;
start slave;#可以查看slave状态
mysql> show slave status\G;
*************************** 1. row ***************************Slave_IO_State: Waiting for master to send eventMaster_Host: 192.168.220.10Master_User: replMaster_Port: 3306Connect_Retry: 60Master_Log_File: mysql-bin.000001Read_Master_Log_Pos: 1481Relay_Log_File: node3-relay-bin.000002Relay_Log_Pos: 320Relay_Master_Log_File: mysql-bin.000001Slave_IO_Running: YesSlave_SQL_Running: Yes            #看到两个线程双Yes则配置成功#主从搭建好之后把主库解表
mysql> unlock tables;

3、SQL_delay(延迟复制，给主库上一个保险)

        延迟复制时用来控制sql 线程的，和 i/o 线程无关

        这个延迟复制不是i/o 线程过段时间来复制， i/o 是正常工作的

        是日志已经保存在slave 端了，那个 sql 要等多久进行回放

步骤如下

        1）先停止从库SQL线程

        2）设置master_delay

        3）重新启动SQL线程 

#将node3配置为延迟复制从库
#停止SQL线程
STOP SLAVE SQL_THREAD;#修改master_delay时间
CHANGE MASTER TO MASTER_DELAY=60;#开启SQL线程
START SLAVE SQL_THREAD;#在show slave status;内容里看到以下内容就配置成功SQL_Delay: 60

4、慢查询日志

•  慢查询，顾名思义，执行很慢的查询
• 当执行 SQL 超过 long_query_time 参数设定的时间阈值（默认 10s ）时，就被认为是慢查询，这个 SQL语句就是需要优化的
• 慢查询被记录在慢查询日志里
• 慢查询日志默认是不开启的
• 如果需要优化 SQL 语句，就可以开启这个功能，它可以让你很容易地知道哪些语句是需要优化的。

#慢查询日志默认不开启
mysql> show variables like "slow%";
+---------------------+----------------------------+
| Variable_name       | Value                      |
+---------------------+----------------------------+
| slow_launch_time    | 2                          |
| slow_query_log      | OFF                        |
| slow_query_log_file | /data/mysql/node1-slow.log |
+---------------------+----------------------------+
3 rows in set (0.00 sec)#慢查询默认查询时间为10s
mysql> show variables like "long%";
+-----------------+-----------+
| Variable_name   | Value     |
+-----------------+-----------+
| long_query_time | 10.000000 |
+-----------------+-----------+
1 row in set (0.00 sec)#开启慢查询日志,两种方法，一种通过命令行，一种通过修改配置参数，以下是命令行
set global slow_query_log=on#验证慢查询日志是否开启
mysql> show variables like "slow%";
+---------------------+----------------------------+
| Variable_name       | Value                      |
+---------------------+----------------------------+
| slow_launch_time    | 2                          |
| slow_query_log      | ON                         |
| slow_query_log_file | /data/mysql/node1-slow.log |
+---------------------+----------------------------+
3 rows in set (0.00 sec)#慢查询日志记录在slow_query_log_file所对应的位置/data/mysql/node1-slow.log里

5、并行复制

        默认情况下slave 中使用的是 sql 单线程回放 ，在master 中时多用户读写，如果使用 sql 单线程回放那么会造成组从延迟严重，开启MySQL 的多线程回放可以解决上述问题

#查看默认情况下slave的线程情况
mysql> show processlist;
+----+-------------+-----------+------+---------+------+--------------------------------------------------------+------------------+
| Id | User        | Host      | db   | Command | Time | State                                                  | Info             |
+----+-------------+-----------+------+---------+------+--------------------------------------------------------+------------------+
|  2 | root        | localhost | db1  | Query   |    0 | starting                                               | show processlist |
|  5 | system user |           | NULL | Connect | 4022 | Waiting for master to send event                       | NULL             |
|  7 | system user |           | NULL | Connect | 2911 | Slave has read all relay log; waiting for more updates | NULL             |
+----+-------------+-----------+------+---------+------+--------------------------------------------------------+------------------+
3 rows in set (0.00 sec)#将node2设定为多线程回放
slave-parallel-type=LOGICAL_CLOCK  #基于组提交
slave-parallel-workers=16          #开启的线程数量
master_info_repository=TABLE       #将master信息记录在表中，默认记录/data/mysql/master_info
relay_log_info_repository=TABLE    #将回放日志信息记录在表中，默认记录在/data/mysql目录下
relay_log_recovery=ON              #日志回放恢复功能开启#查看修改过后slave的线程情况
mysql> show processlist;
+----+-------------+-----------+------+---------+------+--------------------------------------------------------+------------------+
| Id | User        | Host      | db   | Command | Time | State                                                  | Info             |
+----+-------------+-----------+------+---------+------+--------------------------------------------------------+------------------+
|  1 | system user |           | NULL | Connect |    5 | Waiting for master to send event                       | NULL             |
|  2 | system user |           | NULL | Connect |    5 | Slave has read all relay log; waiting for more updates | NULL             |
|  3 | system user |           | NULL | Connect |    5 | Waiting for an event from Coordinator                  | NULL             |
|  4 | system user |           | NULL | Connect |    5 | Waiting for an event from Coordinator                  | NULL             |
|  5 | system user |           | NULL | Connect |    5 | Waiting for an event from Coordinator                  | NULL             |
|  7 | system user |           | NULL | Connect |    5 | Waiting for an event from Coordinator                  | NULL             |
|  8 | system user |           | NULL | Connect |    5 | Waiting for an event from Coordinator                  | NULL             |
|  9 | system user |           | NULL | Connect |    5 | Waiting for an event from Coordinator                  | NULL             |
| 10 | system user |           | NULL | Connect |    5 | Waiting for an event from Coordinator                  | NULL             |
| 11 | system user |           | NULL | Connect |    5 | Waiting for an event from Coordinator                  | NULL             |
| 12 | root        | localhost | NULL | Query   |    0 | starting                                               | show processlist |
+----+-------------+-----------+------+---------+------+--------------------------------------------------------+------------------+
11 rows in set (0.00 sec)

#在所有节点上开启gtid
[root@node1 ~]# vim /etc/my.cnf
[mysqld]
datadir=/data/mysql
socket=/data/mysql/mysql.sock
symbolic-links=0
log-bin=mysql-bin
server-id=1
gtid-mode=on                #以下两行内容，开始gtid
enforce-gtid-consistency=on#从库操作皆以node2为例
mysql> stop slave;
mysql> change master to master_host='192.168.220.10',master_user='repl',master_password='Mysql@123',master_auto_position=1;
mysql> start slave;#检验
mysql> show slave status \G;
*************************** 1. row ***************************Slave_IO_State: Waiting for master to send eventMaster_Host: 192.168.220.10Master_User: replMaster_Port: 3306Connect_Retry: 60Master_Log_File: mysql-bin.000003Read_Master_Log_Pos: 154Relay_Log_File: node2-relay-bin.000002Relay_Log_Pos: 367Relay_Master_Log_File: mysql-bin.000003Slave_IO_Running: YesSlave_SQL_Running: Yes            #出现双Yes代表主从没问题Replicate_Do_DB: Replicate_Ignore_DB: Replicate_Do_Table: Replicate_Ignore_Table: Replicate_Wild_Do_Table: Replicate_Wild_Ignore_Table: Last_Errno: 0Last_Error: Skip_Counter: 0Exec_Master_Log_Pos: 154Relay_Log_Space: 574Until_Condition: NoneUntil_Log_File: Until_Log_Pos: 0Master_SSL_Allowed: NoMaster_SSL_CA_File: Master_SSL_CA_Path: Master_SSL_Cert: Master_SSL_Cipher: Master_SSL_Key: Seconds_Behind_Master: 0
Master_SSL_Verify_Server_Cert: NoLast_IO_Errno: 0Last_IO_Error: Last_SQL_Errno: 0Last_SQL_Error: Replicate_Ignore_Server_Ids: Master_Server_Id: 1Master_UUID: 7ead7e03-687d-11ef-8256-000c298c629aMaster_Info_File: /data/mysql/master.infoSQL_Delay: 0SQL_Remaining_Delay: NULLSlave_SQL_Running_State: Slave has read all relay log; waiting for more updatesMaster_Retry_Count: 86400Master_Bind: Last_IO_Error_Timestamp: Last_SQL_Error_Timestamp: Master_SSL_Crl: Master_SSL_Crlpath: Retrieved_Gtid_Set: Executed_Gtid_Set: Auto_Position: 1            #出现这个则表示gtid模式成功开启Replicate_Rewrite_DB: Channel_Name: Master_TLS_Version: 
1 row in set (0.00 sec)