linux下mysql5.7.24主从、双主从基本配置

主从

一、环境

        主机： master操作系统：centos 7 64位

                   IP：192.168.190.128

                   MySQL版本：5.7.24

         从机：  slave操作系统：centos 7 64位

                   IP：192.168.190.130

                   MySQL版本：5.7.24

         mysql已配置开机自启和环境变量。

二、创建数据库

分别登录master机和slave机的mysql：mysql –u root –p

创建数据库：create database test

三、master、slave修改mysql的 my.cnf 配置文件

    3.1、master数据库参数配置（主、从机配置的不同主要体现在service-id上）

[root@localhost /]# vi /etc/my.cnf
[mysqld]
bind-address = 0.0.0.0

#master
server-id=1
log-bin=mysql-bin
log-bin-index=mysql-bin.index
log-slave-updates=1
binlog-do-db=test
binlog-ignore-db=mysql
binlog_format=mixed
expire_logs_days=7

#mysql
datadir=/usr/local/mysql/data
basedir=/usr/local/mysql/
socket=/tmp/mysql.sock
user=mysql
port=3306
character-set-server=utf8


!includedir /etc/my.cnf.d

      然后重启mysql服务并登陆本机mysql；

[root@localhost ~]# service mysqld restart
Shutting down MySQL.. SUCCESS! 
Starting MySQL. SUCCESS! 
[root@localhost ~]# mysql -uroot -p
Enter password

      查看master机状态，并记住file和position参数，配置slave机时需要用到

mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000006 |      154 | test         |                  |                   |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)

   为slave创建对应权限的账号，并查看。（在主从同步时从机需连接主机）

mysql> grant replication slave on *.* to 'test'@'192.168.190.130' identified by '123456';
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> flush  privileges;
Query OK, 0 rows affected (0.01 sec)

mysql> select user,host  from mysql.user;
+---------------+-----------------+
| user          | host            |
+---------------+-----------------+
| test          | 192.168.190.130 |
| mysql.session | localhost       |
| mysql.sys     | localhost       |
| root          | localhost       |
+---------------+-----------------+
4 rows in set (0.00 sec)

3.2、slave数据库参数配置

[root@localhost /]# vi /etc/my.cnf
[mysqld]
bind-address = 0.0.0.0

#slave
server-id=2
log-bin= mysql-bin
relay-log= mysql-relay-bin
read-only=1
log-slave-updates=1
replicate-do-db=test

#mysql
datadir=/usr/local/mysql/data
basedir=/usr/local/mysql/
socket=/tmp/mysql.sock
user=mysql
port=3306
character-set-server=utf8

!includedir /etc/my.cnf.d

    重启数据库，并尝试在slave连接master机mysql。

[root@localhost /]# service mysqld restart
Shutting down MySQL.. SUCCESS! 
Starting MySQL. SUCCESS! 
[root@localhost /]# mysql -h192.168.190.128 -uroot -p
Enter password: 
ERROR 2003 (HY000): Can't connect to MySQL server on '192.168.190.128' (113)

有报错，提示无法连接，我们尝试关闭master防火墙，并在slave上重新尝试连接。

   master关闭防火墙

[root@localhost ~]# service firewalld stop;
Redirecting to /bin/systemctl stop firewalld.service

   slave重新连接

[root@localhost /]# mysql -h192.168.190.128 -utest -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 7
Server version: 5.7.24-log MySQL Community Server (GPL)

Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql>

slave账号连接成功。

四，在slave数据库设置Slave复制参数

mysql> CHANGE MASTER TO MASTER_HOST='192.168.190.128',MASTER_USER='test',MASTER_PASSWORD='123456',MASTER_PORT=3306,MASTER_LOG_FILE='mysql-bin.000006',MASTER_LOG_POS=154,MASTER_CONNECT_RETRY=10;
Query OK, 0 rows affected, 2 warnings (0.01 sec)

   在slave数据库启动slave，并查看slave状态(Slave_IO_Running和Slave_SQL_Running参数为Yes说明启动成功)(部分参数)

mysql> start slave;
Query OK, 0 rows affected (0.00 sec)

mysql> show slave status \G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.190.128
                  Master_User: test
                  Master_Port: 3306
                Connect_Retry: 10
              Master_Log_File: mysql-bin.000008
          Read_Master_Log_Pos: 154
               Relay_Log_File: mysql-relay-bin.000004
                Relay_Log_Pos: 367
        Relay_Master_Log_File: mysql-bin.000008
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
              Replicate_Do_DB: test

  配置成功，如果同步期间出现错误，需停止slave，清除slave错误信息，然后重启slave；

mysql> stop slave;
Query OK, 0 rows affected (0.00 sec)

mysql> set global sql_slave_skip_counter=1;
Query OK, 0 rows affected (0.00 sec)

mysql> start slave;

双主

双主原理和主从一样，两台mysql互为主从。

上面已经配置了主从同步，现在我们需要在master机上面配置slave参数，然后启动slave，在这之前我们需要先配置一下主、从机的/etc/my.cnf文件。

一、master、slave数据库添加主键自增参数。

[root@localhost /]# vi /etc/my.cnf
[mysqld]
bind-address = 0.0.0.0

#master
server-id=1
log-bin=mysql-bin
log-bin-index=mysql-bin.index
log-slave-updates=1
binlog-do-db=test
binlog-ignore-db=mysql
binlog_format=mixed
expire_logs_days=7
#主键自增规则，避免主从同步时id重复
auto_increment_increment=2  #自增长值，几台mysql。
auto_increment_offset=1     #自增长初始值，主库是1，从库是2

#mysql
datadir=/usr/local/mysql/data
basedir=/usr/local/mysql/
socket=/tmp/mysql.sock
user=mysql
port=3306
character-set-server=utf8


!includedir /etc/my.cnf.d

二、分别重启master、slave   mysql服务。

三、将上方第一步中将主机、从机身份互换，然后重复上方第三步（修改完配置文件）之后的操作，在主机中给从机配置slave账号，并关闭主机防火墙，然后在从机中设置Slave复制参数，然后启动slave。

 

参考资料：https://www.cnblogs.com/liaojie970/p/6198547.html

                  https://www.jianshu.com/p/9538753376bb