mysql 主从及配置


MySQL从库上有一个IO线程负责从主库取binlog到写到本地。另外有一个SQL线程负责执行这些本地日志,实现命令重放;
一、环境
主机:
master操作系统:centos 5.3
IP:192.168.1.222
MySQL版本:5.0.77
从机:
slave操作系统:centos 5.3
IP:192.168.1.220
MySQL版本:5.0.77






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 repl;






三、master机和slave机的相关配置
1、修改master机器中mysql配置文件my.cnf,该文件在/etc目录下
在[mysqld]配置段添加如下字段
server-id=1
log-bin=log
binlog-do-db=repl //需要同步的数据库,如果没有本行,即表示同步所有的数据库
binlog-ignore-db=mysql //被忽略的数据库

在master机上为slave机添加一同步帐号
grant replication slave on *.* to 'repl'@'192.1681.220' identified by '123456';

重启master机的mysql服务:service mysqld restart

用show master status 命令看日志情况
mysql>show master status;
+-----------------+------------+-------------------+-----------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+-----------------+------------+-------------------+-----------------------+
| log.000003 | 98 | repl | mysql |
+-----------------+------------+-------------------+-----------------------+
1 row in set (0.00 sec)







2、修改slave机中mysql配置文件
同样在[mysqld]字段下添加如下内容
server-id=2
master-host=192.168.1.222
master-user=repl
master-password=123456
master-port=3306
master-connect-retry=60
# 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)
#replicate-do-db=repl //同步的数据库(需要备份的数据库名),不写本行 表示 同步所有数据库

然后重启slave机的mysql

在slave机中进入mysql
mysql>start slave;
mysql>show slave status\G;
如果Slave_IO_Running、Slave_SQL_Running状态为Yes则表明设置成功。






四、出现的问题
当我在执行start slave这条命令时,系统提示
ERROR 1200 (HY000): The server is not configured as slave; fix in config file or with CHANGE MASTER TO,
执行show slave status;又提示Empty set (0.00 sec),想不通问题在哪里

后来发现,原来slave已经默认开启,要先关闭再开启
执行 slave stop;
再执行
change master to master_host='192.168.1.222',master_user='repl',master_password='123456', master_log_file='log.000003' ,master_log_pos=98;
然后执行 slave start;
这时 再执行show slave status\G
显示如下:
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.1.222
Master_User: repl
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: log.000003
Read_Master_Log_Pos: 98
Relay_Log_File: mysqld-relay-bin.000002
Relay_Log_Pos: 229
Relay_Master_Log_File: log.000003
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: 98
Relay_Log_Space: 229
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)
显示红色那两行,说明配置成功。






五、测试主从服务器是否能同步
在主服务器上面新建一个表,必须在repl数据下
mysql> use repl
Database changed
mysql> create table test(id int,name char(10));
Query OK, 0 rows affected (0.00 sec)

mysql> insert into test values(1,'zaq');
Query OK, 1 row affected (0.00 sec)

mysql> insert into test values(1,'xsw');
Query OK, 1 row affected (0.00 sec)

mysql> select * from test;
+------+------+
| id | name |
+-------+------+
| 1 | zaq |
| 1 | xsw |
+-------+------+
2 rows in set (0.00 sec)



在从服务器查看是否同步过来
mysql> use repl;
Database changed
mysql> select * from test;
+------+------+
| id | name |
+------+------+
| 1 | za

posted @ 2014-07-21 13:58  三六五  阅读(168)  评论(0编辑  收藏  举报