mysql 主从同步

浏览数：31 / 时间：2015年06月12日

参考：http://blog.csdn.net/dbaxiaosa/article/details/22421969

master配置：

[mysqld]

datadir=/var/lib/mysql

socket=/var/lib/mysql/mysql.sock

user=mysql

# Disabling symbolic-links is recommended to prevent assorted security risks

symbolic-links=0

default-time-zone = ‘+8:00‘

innodb_additional_mem_pool_size = 512M

innodb_buffer_pool_size = 4G

innodb_thread_concurrency = 32

innodb_log_buffer_size = 256M

innodb_flush_log_at_trx_commit = 0

log-bin=mysql-bin

server-id=1121

#binlog-do-db=mysql,maillog,mailmanage

#binlog-ignore-db=syslog,information_schema #忽略同步binlog

[mysqld_safe]

log-error=/var/log/mysqld.log

pid-file=/var/run/mysqld/mysqld.pid

slave配置：

[mysqld]

datadir=/opt/mysql

socket=/var/lib/mysql/mysql.sock

user=mysql

# Disabling symbolic-links is recommended to prevent assorted security risks

symbolic-links=0

log-bin=mysql-bin

server-id=184

replicate-ignore-db=syslog ##忽略master上关于syslog库的同步

# Disabling symbolic-links is recommended to prevent assorted security risks

symbolic-links=0

default-time-zone = ‘+8:00‘

innodb_additional_mem_pool_size = 512M

innodb_buffer_pool_size = 4G

innodb_thread_concurrency = 32

innodb_log_buffer_size = 256M

innodb_flush_log_at_trx_commit = 0

[mysqld_safe]

log-error=/var/log/mysqld.log

pid-file=/var/run/mysqld/mysqld.pid

操作步骤：
1，master锁表

mysql> FLUSH TABLES WITH READ LOCK; ### 锁表

Query OK, 0 rows affected (0.00 sec)

mysql> show master status \G
*************************** 1. row ***************************
            File: mysql-bin.000003
        Position: 1068735    ##slave同步时使用
    Binlog_Do_DB:
Binlog_Ignore_DB:
1 row in set (0.00 sec)

2，master上mysqldump备份为sql文件

mysqldump -uroot -p -B maillog（库名） > /root/maillog.sql

3，master解锁

mysql>UNLOCK TABLES;

4，master授权

mysql>GRANT REPLICATION SLAVE ON *.* to ‘账号‘@‘ip‘ identified by ‘密码‘;

5，scp备份的sql文件到slave主机

6，slave导入

]#mysql -uroot -p maillog < /root/maillog.sql

7，slave开启同步:

mysql>change master to master_host=‘masterIP‘,master_user=‘授权账号‘,master_password=‘授权密码‘,master_log_file=‘mysql-bin.000003‘,master_log_pos=1068735;

mysql>start slave；

mysql>show slave status\G ##重点查看以下绿色部分，双Yes

*************************** 1. row ***************************

Slave_IO_State: Waiting for master to send event

Master_Host: 192.168....

Master_User: mysync

Master_Port: 3306

Connect_Retry: 60

Master_Log_File: mysql-bin.000009

Read_Master_Log_Pos: 903745163

Relay_Log_File: mysqld-relay-bin.000030

Relay_Log_Pos: 903745308

Relay_Master_Log_File: mysql-bin.000009

Slave_IO_Running: Yes

Slave_SQL_Running: Yes

Replicate_Do_DB:

Replicate_Ignore_DB: syslog

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: 903745163

Relay_Log_Space: 903745507

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:

1 row in set (0.00 sec)

说明：
Slave_IO_Running――此进程负责从Slave从Master上读取binlog日志，并写入Slave上的中继日志。
Slave_SQL_Running――此进程负责读取并执行中继日志中的binlog日志。
这两个进程的状态需全部为YES，只要有一个为NO，则复制就会停止。
当Slave中Relay_Master_Log_File和Master_Log_File相同且Read_Master_Log_Pos和Exec_Master_Log_Pos完全相同时，则表明Slave和Master处于完全同步的状态。

8，验证

master创建一个空库，查看slave能否同步

分别在主从服务器show processlist查看连接，就可以看到授权用户的连接，可证明复制已经生效。

9，监控slave同步异常：

[root@localhost ~]# more /usr/local/bin/check_mysql_slave

#!/bin/sh

D=`date +%Y%m%d:%T`

declare -a slave_is

slave_is=($(mysql -uroot -p密码 -e "show slave status\G"|grep Running|awk ‘{print $2}‘))

if [ "${slave_is[0]}" = "Yes" -a "${slave_is[1]}" = "Yes" ];then

exit 0

else