分类： Mysql/postgreSQL
2011-11-17 16:53:25
Mysql5.5.13版本主从同步配置方法
测试环境主服务器IP：192.168.0.202(MYSQL:5.5.13、OS:Redhat as 6.0)
从服务器IP：192.168.0.210(MYSQL:5.5.13、OS:Redhat as 6.0)
注:此文档只描述主à从 的同步，而不是互备。要保证主从服务器的配置文件一致（仅仅server-id不一样，从服务器定义不要repl的数据库名称）
如需要达到互备效果，而在操作完整个文档内容后，执行下面两步即可：
1. 在从机上执行：mysql> grant replication slave on *.* to rep2@192.168.0.202 identified by 'password';
2. 在主机上执行：start slave
开始配置主从服务器：l 主服务器配置：
主服务器上的配置和低版本的配置方式一样，只需要在配置文件中开启二进制日志文件和设置server-id=1。
编辑mysql配置文件/etc/my.cnf，在[mysqld]部分加入：
server-id=1
log-bin=/data/binlog/binlog.bin（binlog存放的地方）
在主服务器上建立一个从服务器进行复制使用的账户(用户名：rep；密码：*********)：
mysql> grant replication slave on *.* to rep@192.168.0.210 identified by '********';
mysql> flush privileges;
重启mysql服务
# /usr/loca/mysql/bin/mysqladmin shutdown
#/usr/local/mysql/bin/mysqld_safe &
l 从服务器配置：
Mysql5.1.7版本以后已经不支持把master配置属性写在my.cnf文件中了，只能把需要同步的数据库和需要忽略的数据库加入。
编辑从服务器的mysql配置文件/etc/my.cnf，在[mysqld]部分加入：
server-id=2
log-bin=/logdata/binlog/binlog.bin
replicate-do-db=db_name #这两条最好加在结尾[需要同步的数据库]
replicate-ignore-db=mysql #这两条最好加在结尾[不需要同步的库]
replicate-ignore-db=test #一般将mysql与test这两个库取消不要同步，保证业务使用的数据库即可
重启mysql服务。
进入mysql命令行，停止从服务器线程并执行mysql命令，然后再启动从服务器线程：
mysql> stop slave;
Query OK, 0 rows affected (0.01 sec)
mysql> change master to
-> master_host='192.168.0.202',
-> master_user='root',
-> master_password='password';
Query OK, 0 rows affected (0.01 sec)
mysql> start slave;
从服务器上检查复制进程是否正确：
mysql> show slave status \G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.0.202
Master_User: rep
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: binlog.000022
Read_Master_Log_Pos: 1206606
Relay_Log_File: test-file01-relay-bin.000008
Relay_Log_Pos: 666782613
Relay_Master_Log_File: binlog.000007
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB: mysql,test
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: 666782470
Relay_Log_Space: 7793804982
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: 6055915
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)
上面出现： Slave_IO_Running: Yes 和 Slave_SQL_Running: Yes 表示复制正常，如果有一个显示是NO，请检查以上的主从设置步骤是否正确。如果出现复制错误，从服务器的错误日志中也会出现错误消息。
主从复制异常处理l Slave_IO异常
通过show slave status \G;
看到slave_IO出现异常；
Slave_IO_Running:NO
Slave_SQL_Running:Yes
Seconds_Behind_Master: NULL
这个时候在从数据库的日志文件中应该有相应的日志信息，可以通过检查日志看到导致失败的原因；大致可能会有这样两种情况：
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文件异常（比如主库异常，丢失binlog文件等）；
对于第一种情况，仔细检查数据库访问权限即可解决；
通过配置主从步骤，从新设置下grant权限（针对不同用户）
对于第二种情况，详细介绍一下：
mysql> show slave status \G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.0.202
Master_User: rep
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: binlog.000022
Read_Master_Log_Pos: 1206606
Relay_Log_File: test-file01-relay-bin.000008
Relay_Log_Pos: 666782613
Relay_Master_Log_File: binlog.000007
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB: mysql,test
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: 666782470
Relay_Log_Space: 7793804982
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: 6055915
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)
[root@test-file01 data]# tail -f test-file01.err
111117 15:15:23 [Note] Slave: received end packet from server, apparent master
shutdown:
111117 15:15:23 [Note] Slave I/O thread: Failed reading log event, reconnecting to retry, log 'binlog.000022' at position 1760927
111117 15:15:23 [ERROR] Slave I/O: error reconnecting to master 'rep@192.168.0.202:3306' - retry-time: 60 retries: 86400, Error_code: 2003
111117 15:24:23 [Note] Slave: connected to master 'rep@192.168.0.202:3306',replication resumed in log 'binlog.000022' at position 1760927
111117 15:35:55 [Note] Slave: received end packet from server, apparent master shutdown:
111117 15:35:55 [Note] Slave I/O thread: Failed reading log event, reconnecting to retry, log 'binlog.000023' at position 377015
111117 15:35:55 [ERROR] Slave I/O: error reconnecting to master 'rep@192.168.0.202:3306' - retry-time: 60 retries: 86400, Error_code: 2003
111117 15:37:55 [Note] Slave: connected to master 'rep@192.168.0.202:3306',replication resumed in log 'binlog.000023' at position 377015
111117 15:37:55 [ERROR] Error reading packet from server: Client requested master to start replication from impossible position ( server_errno=1236)
111117 15:37:55 [ERROR] Slave I/O: Got fatal error 1236 from master when reading data from binary log: 'Client requested master to start replication from impossible position', Error_code: 1236
111117 15:37:55 [Note] Slave I/O thread exiting, read up to log 'binlog.000023', position 377015
解决步骤：
重启master库：service mysqld restart
mysql> show master status;
+---------------+----------+--------------+------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+---------------+----------+--------------+------------------+
| binlog.000023 | 4157716 | | |
+---------------+----------+--------------+------------------+
1 row in set (0.01 sec)mysql> slave stop;
mysql> change master to Master_Log_File='binlog.000023',Master_Log_Pos=3436946;
msql> slave start;
mysql> show slave status \G;
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.0.202
Master_User: rep
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: binlog.000023
Read_Master_Log_Pos: 4157716
Relay_Log_File: test-file01-relay-bin.000002
Relay_Log_Pos: 721020
Relay_Master_Log_File: binlog.000023
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB: mysql,test
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: 4157716
Relay_Log_Space: 721182
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)
ERROR:
No query specified
