mysq的主从复制、备份、还原

搭建实验环境说明：

在 RH5.4 yum安装 mysql部署master 数据库A，Centos 5.5 编译安装mysql 部署slave数据库B；

mysql 版本信息：

 master  mysql-5.0.77    slave ：mysql-5.0.87        //测试环境并没有考虑版本问题

提示：（关闭selinux）

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一般情况：mysqladmin -uroot password '123456'设置root用户访问mysql的密码；
mysql -uroot -p 键如密码即可登录mysql>界面

一、

##########################在master mysql操作：##########################
1、授权从服务器的root用户来主服务器同步资源的权限
mysql> GRANT REPLICATION SLAVE,REPLICATION CLIENT,RELOAD,SUPER ON *.* TO root#slave IP     IDENTIFIED BY '123456';             //将#换成@

#如果需要的话添加管理用户，通过mysql的客户端来测试同步的情况

mysql>flush privileges;                                           // 刷新权限，使设置生效

#在node2上使用一下命令测试授权是否成功

#mysql -h 192.168.0.42 -uroot -p

2、在master mysql 配置
#vim /etc/my.cnf

# 确保有如下行
server-id = 1
log-bin=mysql-bin
binlog-do-db=mytest
binlog-ignore-db=mysql
#binlog-do-db=                                    // 需要备份的数据库名，可写多行
#binlog-ignore-db=                             // 不需要备份的数据库名，可写多行

二、
##########################在slave mysql操作：###########################

1、编辑/etc/my.cnf
server-id=2
log-bin=mysql-bin
master-host=192.168.0.123
master-user=root

master-password=123456
master-port=3306
replicate-do-db=mytest
可选项如下：
# replicate-do-db=test                               //  需要备份的数据库名
# replicate-ignore-db=mysql                        //  忽略的数据库
# master-connect-retry=60        //如果从服务器发现主服务器断掉，重新连接的时间差(秒)

三、

##########################在master mysql操作：##########################

1、创建测试数据库

mysql> create database mytest;                      //创建mytest库
mysql>show databases;
mysql> use mytest;            

mysql> show tables;

+------------------+
| Tables_in_mytest |
+------------------+
| mytable                   |
+------------------+
1 row in set (0.01 sec)

mysql>ceate table mytable (name VARCHAR(20), sex CHAR(1), birth DATE, birthaddr VARCHAR(20));
mysql>describe mytable; 

mysql>insert into mytable values   ('hanfeng','b','1987-08-08','china'); 

mysql>insert into mytable values   ('feiniao','g','1988-08-08','china');

mysql>select * from mytable;

+----------+------+------------+-----------+
| name     | sex  | birth      | birthaddr |
+----------+------+------------+-----------+
| hanfeng  | s    | 1985-08-08 | china     |
| feiniao  | g    | 1988-08-08 | china     |
+----------+------+------------+-----------+

 

2、在master使用mysqldump命令将数据库导出：

#mysqldump -uroot mytest  > mysql.sql

3、使用scp命令将mysql.sql拷贝到slave

#scp mysq.sql root#slaveIP:/root                 //将#换成@

四、

##########################在slave mysql操作：###########################

1、创建mytest数据库，

mysql> create database mytest；

2、将mysql.sql导入其中
#mysql -uroot -p mytest < mysql.sql

3、检查mysql.sql导入是否成功

mysql> create database mytest;                        

mysql>show databases;
mysql> use mytest;            

mysql> show tables;

+------------------+
| Tables_in_mytest |
+------------------+
| mytable            |
+------------------+

mysql>select * from mytable;

+----------+------+------------+-----------+
| name     | sex  | birth      | birthaddr |
+----------+------+------------+-----------+
| hanfeng  | s    | 1985-08-08 | china     |
| feiniao  | g    | 1988-08-08 | china     |
+----------+------+------------+-----------+

 

4、验证配置的正确性

mysql>start slave；                    // 如果启动失败，参看以下错误处理②
mysql> show slave status\G;
*************************** 1. row *******************
Slave_IO_State: Waiting for master to send event 必须的
Master_Host: 192.168.0.123
Master_User: root

Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000002
Read_Master_Log_Pos: 287
Relay_Log_File: mysqld-relay-bin.000009
Relay_Log_Pos: 424
Relay_Master_Log_File: mysql-bin.000002
Slave_IO_Running: Yes      # 为YES状态  （说明：如果出现NO请参看下面错误解答！）
Slave_SQL_Running: Yes   # 为YES状态
Replicate_Do_DB: mytest
Replicate_Ignore_DB:

#####################################################################

                                      此时使用mysqldump的备份与还原基本完成

五、
##########################在master mysql操作：##########################
mysql> use mytest;
mysql>insert into mytable values  ('shanghai','s','2011-09-13','china');

mysql>select * from mytable;
向mytest数据库的mytable表中插入一新记录；
在slave服务器上
mysql> use mytest;
mysql>select * from mytable;
得到：
mysql> select * from mytable;
+-----------+------+------------+---------------+
| name      | sex  | birth      | birthaddr       |
+-----------+------+------------+----------------+
| hanfeng   | b    | 1987-08-08 | china       |
| feiniao     | g    | 1988-08-08 | china        |
| shanghai | s    | 2011-09-13 | china     |
+-----------+------+------------+---------------+
 3 rows in set (0.01 sec)

 基于mysql数据库文件的主从同步与AB复制及数据备份到此完成！

 

总结：

##############################  错误处理 ① ##########################

对于       Slave_IO_Running: No
               Slave_SQL_Running: Yes
错误解答

Master slave 复制错误
Description：
Slave_IO_Running:NO
Slave_SQL_Running:Yes
Seconds_Behind_Master: NULL
本人遇到的Slave_IO_Running:NO的情况有下面两种：
1. 在配置slave同步时因为slave访问master没有权限导致；
2. master上的mysql-bin.xxxxxx文件全被我误删除了；
对于第一种情况，仔细检查数据库访问权限即可解决；
对于第二种情况：
mysql> show slave status\G
*************************** 1. row ***************************
             Slave_IO_State:
                Master_Host: 192.168.0.123
                Master_User: slave
                Master_Port: 3306
              Connect_Retry: 60
            Master_Log_File: mysql-bin.000016
        Read_Master_Log_Pos: 173
             Relay_Log_File: mysqld-relay-bin.000008
              Relay_Log_Pos: 98
      Relay_Master_Log_File: mysql-bin.000016
           Slave_IO_Running: No
          Slave_SQL_Running: Yes
            Replicate_Do_DB:
        Replicate_Ignore_DB:
         Replicate_Do_Table:
     Replicate_Ignore_Table: br>          

                  Last_Error: 0
               Skip_Counter: 0
        Exec_Master_Log_Pos: 173
            Relay_Log_Space: 98
            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: NULL
1 row in set (0.00 sec)

解决步骤：
重启master库：service mysqld restart
mysql> show master status;
+------------------+--------------------+----------------+------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+-------------------+-----------------+------------------+
| mysql-bin.000001 |       98 |              |                                         |
+------------------+--------------------+-----------------+------------------+
mysql> slave stop;
mysql> change master to Master_Log_File='mysql-bin.000001',Master_Log_Pos=98;
mysql> slave start;
mysql> show slave status\G
*************************** 1. row ***************************
             Slave_IO_State: Waiting for master to send event
                Master_Host: 192.168.0.123
                Master_User: slave
                Master_Port: 3306
              Connect_Retry: 60
            Master_Log_File: mysql-bin.000001
        Read_Master_Log_Pos: 98
             Relay_Log_File: mysqld-relay-bin.000002
              Relay_Log_Pos: 235
      Relay_Master_Log_File: mysql-bin.000001
           Slave_IO_Running: Yes
          Slave_SQL_Running: Yes
            Replicate_Do_DB:
    Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
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: 98
            Relay_Log_Space: 235
            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
1 row in set (0.00 sec)

##############################  错误处理 ② ##########################

问题：如果你的mysql数据库已经有数据存储使用，将导致master与slave日志错误！
mysql> start slave;
ERROR 1201 (HY000): Could not initialize master info structure; more error messages can be found in the MySQL error log
mysql> show slave status;
Empty set (0.00 sec)

处理：删除mysql-bin.000001 日志文件，并重启mysql服务
1、master
#rm -rf /var/lib/mysql/*.*        
2、slave
#rm -rf /usr/local/mysql/var/*.*   
3、service mysqld restart