系统版本

CentOS Linux release 7.6.1810 (Core)

安装mysql

yum localinstall http://dev.mysql.com/get/mysql57-community-release-el7-7.noarch.rpm
yum install mysql-community-server

启动数据库

systemctl start mysqld

使用命令获取 mysql 的默认密码。

grep 'temporary password' /var/log/mysqld.log

2020-12-09T16:13:58.575693Z 1 [Note] A temporary password is generated for root@localhost: av*Gtzb7MTy#

登陆数据库：第一次登陆需要更改密码

[root@node01 ~]# mysql -uroot -pav*Gtzb7MTy#
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 4
Server version: 5.7.32

Copyright (c) 2000, 2020, 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> show databases;
ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement.

从新设置密码：

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

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

mysql> alter user 'root'@'localhost' identified by '123456';
Query OK, 0 rows affected (0.00 sec)

主备同步设置：

主配置：

/etc/my.cnf

server-id=1
log-bin=mysql-bin

查看数据库状态：

show variables like 'log_bin';

mysql> show variables like 'log_bin';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| log_bin       | ON    |
+---------------+-------+
1 row in set (0.01 sec)

show master status;

+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000001 |      154 |              |                  |                   |
+------------------+----------+--------------+------------------+-------------------+

主数据库创建同步账号

grant FILE on *.* to 'rep'@'192.168.0.205' identified by '123456';
grant replication slave on *.* to 'rep'@'192.168.0.205' identified by '123456'; 
flush privileges;

从配置：

my.cnf

log-bin=mysql-bin
server-id=2
binlog-ignore-db=information_schema
binlog-ignore-db=performance_schema
binlog-ignore-db=mysql

重启、登录mysql从数据库，mysql5.7以后需要在命令行中配置：

//停止，启动slave进程。

stop slave;

change master to master_host='192.168.0.205',
master_user='rep',
master_password='123456',
master_log_file='mysql-bin.000001', 
master_log_pos=1278;

start slave;

show slave status\G;

mysql> show slave status\G;
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.0.205
                  Master_User: rep
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000001
          Read_Master_Log_Pos: 2338
               Relay_Log_File: node01-relay-bin.000002
                Relay_Log_Pos: 1380
        Relay_Master_Log_File: mysql-bin.000001
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
              Replicate_Do_DB:
          Replicate_Ignore_DB:
           Replicate_Do_Table:
       Replicate_Ignore_Table:
      Replicate_Wild_Do_Table:
  Replicate_Wild_Ignore_Table:
                   Last_Errno: 0
                   Last_Error:
                 Skip_Counter: 0
          Exec_Master_Log_Pos: 2338
              Relay_Log_Space: 1588
              Until_Condition: None
               Until_Log_File:
                Until_Log_Pos: 0
           Master_SSL_Allowed: No
           Master_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: No
                Last_IO_Errno: 0
                Last_IO_Error:
               Last_SQL_Errno: 0
               Last_SQL_Error:
  Replicate_Ignore_Server_Ids:
             Master_Server_Id: 1
                  Master_UUID: 8a59fbeb-3a39-11eb-ac5f-000c29ccec7f
             Master_Info_File: /var/lib/mysql/master.info
                    SQL_Delay: 0
          SQL_Remaining_Delay: NULL
      Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
           Master_Retry_Count: 86400
                  Master_Bind:
      Last_IO_Error_Timestamp:
     Last_SQL_Error_Timestamp:
               Master_SSL_Crl:
           Master_SSL_Crlpath:
           Retrieved_Gtid_Set:
            Executed_Gtid_Set:
                Auto_Position: 0
         Replicate_Rewrite_DB:
                 Channel_Name:
           Master_TLS_Version:
1 row in set (0.00 sec)

ERROR:
No query specified

错误信息：

Last_IO_Error: Fatal error: The slave I/O thread stops because master and slave have equal MySQL server UUIDs; these UUIDs must be different for replication to work.

auto.cnf ==》主备数据库重复

mv /data/mysqldata/auto.cnf  /data/mysqldata/auto.cnf.bk

systemctl restart mysqld

》创建测试数据库检查同步状态；