mysql-主从搭建

环境准备

主机名	IP	系统/MySQL版本	角色
node3	192.168.210.132	CentOS7.3/5.5.60	Master
node2	192.168.210.130	CentOS7.3/5.5.60	slave

一、master节点

1、创建需要同步的数据库

mysql> create database zn;
mysql> use zn;
mysql> create table T1(id int,name varchar(20));

2、停止数据库服务

systemctl stop mariadb.service

3、编辑my.cnf

[mysqld]
log-bin=mysql-bin-master          #启用二进制日志
server-id=1                       #本机数据库ID 标示
binlog-do-db=zn                   #可以被从服务器复制的库, 二进制需要同步的数据库名
binlog-ignore-db=mysql            #不可以被从服务器复制的库

4、重启数据库服务

systemctl restart mariadb.service

5、创建同步用户并授权

MariaDB [(none)]> grant replication slave on *.* to slave@'%'  identified by "123";
MariaDB [(none)]> show master status; 
+-------------------------+----------+--------------+------------------+
| File                    | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+-------------------------+----------+--------------+------------------+
| mysql-bin-master.000001 |      384 | zn           | mysql            |
+-------------------------+----------+--------------+------------------+

MariaDB [(none)]> 
MariaDB [(none)]> 
MariaDB [(none)]> show binlog eventsG
*************************** 1. row ***************************
   Log_name: mysql-bin-master.000001
        Pos: 4
 Event_type: Format_desc
  Server_id: 1
End_log_pos: 245
       Info: Server ver: 5.5.60-MariaDB, Binlog ver: 4
*************************** 2. row ***************************
   Log_name: mysql-bin-master.000001
        Pos: 245
 Event_type: Query
  Server_id: 1
End_log_pos: 384
       Info: grant replication slave on *.* to slave@'%'  identified by "123"
2 rows in set (0.00 sec)

6、查看二进制文件

[root@node3 my.cnf.d]# cd /var/lib/mysql/
[root@node3 mysql]# ls[root@node3 mysql]# ls
aria_log.00000001  ibdata1      ib_logfile1  mysql-bin-master.000001  mysql.sock          test
aria_log_control   ib_logfile0  mysql        mysql-bin-master.index   performance_schema  zn

7、将要同步的数据库导出，并发送给slave节点，复制前要保证同步的数据库一致

mysqldump  -uroot -p123 zn >zn.sql    #可以导出数据库
scp zn.sql  192.168.210.130:/root  

二、slave节点

1、两台数据库服务器mysql版本要一致

MariaDB [(none)]> show variables like '%version%';
+-------------------------+----------------------+
| Variable_name           | Value                |
+-------------------------+----------------------+
| innodb_version          | 5.5.59-MariaDB-38.11 |
| protocol_version        | 10                   |
| slave_type_conversions  |                      |
| version                 | 5.5.60-MariaDB       |
| version_comment         | MariaDB Server       |
| version_compile_machine | x86_64               |
| version_compile_os      | Linux                |
+-------------------------+----------------------+
7 rows in set (0.00 sec)

MariaDB [(none)]> 

2、测试连接到主服务器是否成功，只有复制的权限, 是看不到其他库的

[root@node2 ~]# mysql -uslave -p123 -h 192.168.210.132
MariaDB [(none)]> 
MariaDB [(none)]> 
MariaDB [(none)]> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| test               |
+--------------------+
2 rows in set (0.00 sec)
MariaDB [(none)]> 

3、正常导入数据库，和主数据库服务器保持一致

[root@node2 ~]# mysql -u root
MariaDB [(none)]> create database zn;
Query OK, 1 row affected (0.00 sec)
MariaDB [(none)]> exit
[root@node2 ~]# mysql -uroot zn<zn.sql

4、从服务器没必要开启bin-log日志，修改从服务器配置文件：

[root@node2 ~]# systemctl stop mariadb.service 
[root@node2 ~]# vim /etc/my.cnf
[mysqld]
server-id=2   #从服务器ID号，不要和主ID相同 ，如果设置多个从服务器，每个从服务器必须有一个唯一的server-id值，必须与主服务器的以及其它从服务器的不相同。可以认为server-id值类似于IP地址：这些ID值能唯一识别复制服务器群集中的每个服务器实例。

5、停止slave服务，设置master节点ip，master_user同步用户和密码

[root@node2 ~]# mysql -u root 
MariaDB [(none)]> stop slave;
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]>
MariaDB [(none)]> change master to master_host='192.168.210.132',master_user='slave',master_password='123';
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]> 
MariaDB [(none)]> start slave;
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]>MariaDB [(none)]> show slave statusG
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.210.132
                  Master_User: slave
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin-master.000001
          Read_Master_Log_Pos: 384
               Relay_Log_File: mariadb-relay-bin.000002
                Relay_Log_Pos: 675
        Relay_Master_Log_File: mysql-bin-master.000001
             Slave_IO_Running: Yes            #负责与主机的io通信
            Slave_SQL_Running: Yes            #负责自己的slave mysql进程
              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: 384
              Relay_Log_Space: 971
              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
1 row in set (0.00 sec)

MariaDB [(none)]> 

三、maste节点

（1）再到主服务器上查看状态：

[root@node3 mysql]# mysql -u root
MariaDB [(none)]> show processlistG  
*************************** 1. row ***************************
      Id: 11
    User: slave
    Host: node2:37878
      db: NULL
 Command: Binlog Dump
    Time: 343
   State: Master has sent all binlog to slave; waiting for binlog to be updated
    Info: NULL
Progress: 0.000

（2）同步测试插入数据测试同步：

MariaDB [zn]> select * from T1;
Empty set (0.00 sec)
MariaDB [zn]> 
MariaDB [zn]> insert into T1 values (1,'man');
Query OK, 1 row affected (0.00 sec)

MariaDB [zn]> 
MariaDB [zn]> select * from T1;               
+------+------+
| id   | name |
+------+------+
|    1 | man  |
+------+------+
1 row in set (0.00 sec)

MariaDB [zn]> 

四、slave节点验证数据是否同步

MariaDB [zn]> show tables;     
+-----------------------+
| Tables_in_zn          |
+-----------------------+
| T1                    |
| wp_commentmeta        |
| wp_comments           |
| wp_links              |
| wp_options            |
| wp_postmeta           |
| wp_posts              |
| wp_term_relationships |
| wp_term_taxonomy      |
| wp_terms              |
| wp_usermeta           |
| wp_users              |
+-----------------------+
12 rows in set (0.00 sec)

MariaDB [zn]> 
MariaDB [zn]> select * from T1;
+------+------+
| id   | name |
+------+------+
|    1 | man  |
+------+------+
1 row in set (0.01 sec)

MariaDB [zn]> 

五、如果遇到主从不同步修复

（1）在master节点，看一下主从bin-log的位置，然后再同步

MariaDB [(none)]> show master status; 
+-------------------------+----------+--------------+------------------+
| File                    | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+-------------------------+----------+--------------+------------------+
| mysql-bin-master.000001 |      384 | zn           | mysql            |
+-------------------------+----------+--------------+------------------+
1 row in set (0.00 sec)

MariaDB [(none)]> show binlog eventsG
*************************** 1. row ***************************
   Log_name: mysql-bin-master.000001
        Pos: 4
 Event_type: Format_desc
  Server_id: 1
End_log_pos: 245
       Info: Server ver: 5.5.60-MariaDB, Binlog ver: 4
*************************** 2. row ***************************
   Log_name: mysql-bin-master.000001
        Pos: 245
 Event_type: Query
  Server_id: 1
End_log_pos: 384
       Info: grant replication slave on *.* to slave@'%'  identified by "123"
2 rows in set (0.00 sec)

MariaDB [(none)]> 

（2）slave节点执行MySQL命令下：

MariaDB [(none)]> stop slave;
Query OK, 0 rows affected (0.01 sec)

MariaDB [(none)]> 
MariaDB [(none)]> change master to master_log_file='mysql-bin-master.000002',master_log_pos=245;
Query OK, 0 rows affected (0.01 sec)
#根据上面主服务器的show master status的结果，进行从服务器的二进制数据库记录回归，达到同步的效果
MariaDB [(none)]> MariaDB [(none)]> slave start ;
Query OK, 0 rows affected (0.00 sec)

MariaDB [(none)]> show slave statusG
             Slave_IO_Running: Yes         #如果都是yes，那代表已经在同步
            Slave_SQL_Running: Yes